P 04/02


NMR methods for the characterisation of mass transport and reaction processes in porous materials

The project will aim at developing novel and optimising existing measurement methods of magnetic resonance imaging (MRI) and MR spectroscopic imaging (MRSI) for the non-invasive characterisation of liquids and gases in porous materials. The work will comprise both methodological developments and applications, the latter in close cooperation with other Ph.D. students of the graduate school. All NMR studies will be performed on a 7-Tesla NMR imaging system (Bruker Biospec 70/20 USR) available in the in-vivo-MR group of the department of chemistry of the University of Bremen.

For improved MRI measurements of the distribution of liquids and/or gases in porous samples, methods will be developed that allow to compensate for off-resonance effects introduced by the porous materials dependent on the material properties and pore size distribution or by chemical shift effects. Transport processes will be investigated by fast velocity mapping performed despite short effective transverse relaxation times as well as by quantitative diffusion MRI. This work will be performed in close cooperation with the Ph.D. project on deep bed filtration. For observing catalytic reactions in gases studied in another Ph.D. Project, spectroscopic imaging sequences with minimised echo time, i.e. minimised delay between radiofrequency excitation and data acquisition, will be developed to increase the SNR and allow for detecting species with very short transverse relaxation times. All topics will include work on dedicated software for data quantification. The figure displays results obtained by using an optimised zero echo time MRI sequence as well as the 7-Tesla MRI system available for the projects of the graduate school.

Contact: Dreher , Mirdrikvand