Nuclear Magnetic Resonance, in short NMR is a physical phenomenon with many applications in science, engineering, medicine, and art. Atomic nuclei with appropiate magnetic properties, often 1H or 13C nuclei are probed with radio-frequency waves following alignment with a magnetic field. The most popular uses are Magnetic Resonance Imaging, in short MRI, in medicine and NMR spectroscopy in chemistry. There are many other uses of NMR, and the number of applications is growing, as the instrumentation and the measurement methods are refined. These developments are continuing since the first NMR measurements of condensed matter in 1945.
The members of the Chair of Macromolecular Chemistry, in short MC II, at the Institut für Technische und Makromolekulare Chemie, in short ITMC, of RWTH Aachen University actively contribute to the progress in NMR by specializing in the development and use of NMR to analyze polymer and other materials as well as chemical processes. The Magnetic Resonance Center, in short MARC, of ITMC is one of a few laboratories equipped to perform a broad range of NMR studies in these areas. The NMR machines are empoyed for high-resolution spectroscopy to analyze the structure and dynamics of molecules in solution and in the solid state, for NMR imaging to study the structure of objects like soft matter and the function of heterogeneous chemical processes, and for mobile low-field NMR suitable for non-destructive testing and chemical analyses at the site of interest. This unique combination of equipment and expertise is applied to a broad range of interdisciplinary research projects within ITMC, RWTH Aachen University, international cooperative projects, and industrial collaborations.
NMR imaging, in short MRI
Nuclear magnetic resonance imaging, NMR imaging or by MRI, deals with the visualisation of localized properties of materials, objects, and devices. MRI has the special advantage to give non-invasive and non-destructive insights in both transparent and opaque objects. This way, it allows to monitor a variety of material properties inside the object or interest, such as the homogeneity, composition, and dynamics, as well as the temporal change of these properties.
Typically, the methodology of NMR involves homogeneous magnetic fields generated by strong superconducting magnets. But such large and static devices are inapplicable to in-situ research on large or badly accessible objects, and the size of the sample has to be adjusted to the size of standard NMR probes. Mobile NMR, however, makes use of NMR instrumentation based on portable permanent magnets. Here, the challenge is to compensate for the reduced magnetic field strength and homogeneity, in order to maximize both sensitivity and resolution of NMR experiments. The special advantage of compact NMR is the possibility to adjust the magnet geometry precisely to the position, size and shape of the object of interest. As a result, a multitude of specialized mobile NMR applications has been developed, which pioneer in some areas of research, or even have been established as standard NMR methods.