Current PhD Theses

Jennifer Braun takes a closer look at the sniffer dog as a "detector" for volatile organic compounds (VOCs). Thanks to their highly sensitive olfactory system, sniffer dogs have the special ability to sniff out drugs, explosives, people or animals on the basis of their scent. But how sensitive is the dog and how reliable is its detection? To get to the bottom of this, doctoral student Jennifer Braun is working on methods for the quality-assured quantification of VOCs, which primarily involve instrumental analysis but also the sniffer dog. Supervisor: Prof. Dr. P. Kaul

N-nitrosamines are partly highly volatile compounds that can be formed in many different industrial processes and are classified as carcinogenic. Therefore, it is of acute interest that reliable, sensitive and mobile systems for the detection and quantification of N-nitrosamines are developed. Jana Hinz is working on the development of a GC-FAIMS system, a measuring device for the rapid analysis of N-nitrosamines used in various branches of industry. Compared to common methods, GC-FAIMS offers the advantage of being fast, on-site applicable and cost-efficient. Supervisor: Prof. Dr. M. Wirtz

Raw meat quickly shows bacterial infestation. If the contaminated meat is consumed, it can be hazardous to health if it exceeds a certain quantity. Therefore D. Klein wants to make contaminations (e.g. bacteria) on complex substrates (e.g. meat) visible. To do so, he is linking spectroscopic data from IR and Raman spectroscopy from the same measurement regions to show where contaminations can be found. By linking the two methods, the information content of the data set should increase and at the same time the error rate in contamination detection should decrease. Supervisor: Prof. Dr. P. Kaul

Newly synthesized chemicals or products that pose an explosion hazard in their pure form or as a mixture pose a safety risk without adequate characterization and classification. Classically, such substances are characterized using a variety of conventional test methods that require handling relatively large sample quantities. The aim of Matthias Muhr's PhD project is to develop a testing apparatus that enables a more precise characterization of such substances by sensory monitoring of these conventional methods. In doing so, the sample quantities are to be significantly reduced in order to significantly lower the safety risk during handling.

In recent years, 3D cameras based on the time-of-flight method - also driven by their use in smartphones - have increasingly found their way into our everyday lives. The possible applications of this technology are immense - automatic environment detection in the automotive sector, safety and automation functions in robotics, tasks of automatic area monitoring, biometric problems or the contactless control of technical devices. The aim of M. Rohde's research is to improve these cameras for the use in biometric or outdoor applications. Supervision: Prof. Dr. Robert Lange

Due to its unique properties, ultrapure water is used as a solvent or starting product for pharmaceuticals as well as for cleaning surfaces during manufacture of high-precision components in semiconductor production. Monitoring the quality of the water is of utmost importance here. S. Schäfer is developing a universal measuring device for monitoring ultrapure water quality, combining oxidation by ozonation in combination with UV radiation. This leads to an extended oxidation process and a significant increase in oxidation power compared to conventional systems. Supervisor: Prof. Dr. P. Kaul

The local and controlled initiation of energetic materials by laser radiation coupled with sensory monitoring involves a number of issues and is particularly challenging for ignition materials. The direction of the work is in the area of detection methodology. Here, the controlled coupling of energy by laser radiation (different beam sources) into the investigated substances without knowledge of their specific absorption coefficients is of great interest in the development of detection methods. One possibility to realize this is the application of suitable coatings with known absorption coefficients. For this purpose, different methods (e.g. spray coating) are being comparatively investigated. Thus, in conjunction with the selection of suitable laser parameters, the realization of a controlled local initiation below critical geometries could be achieved, so that the energetic material does not come to the mass for conversion, thus preventing detonation or deflagration. The gases and physical phenomena emitted during the reaction will be used to study the material under investigation and the processes involved. Supervisor: Prof. Dr. Thomas M. Klapötke / Prof. Dr. Peter Kaul

Potato cancer, caused by the potato fungus Synchytrium endobioticum (Schilb.) Perc. is one of the most important pests of potatoes (quarantine status in the EU). Therefore, early detection and containment is extremely important. S. Vermeeren analyses the volatile organic compound (VOC) profiles of potato plants, potatoes and residual soil using thermodesorption gas chromatography-mass spectrometry (TD-GC-MS) and proton transfer reaction time-of-flight mass spectrometry (PTR-ToF-MS), with the aim of being able to distinguish between healthy and infected states. Supervisor: Prof. Dr. P. Kaul