PhD scholarships for natural scientists or engineers

Transcription

1 PhD scholarships for natural scientists or engineers The Braunschweig International Graduate School of Metrology (B-IGSM) offers a structured doctorate in cutting edge research combined with a metrological qualification programme. The graduate school supports its PhD students in acquiring key competences in metrology by offering a curriculum on metrological concepts and research as well as on structures of metrology and regulatory activities. The curriculum is supplemented by workshops, topical courses, international summer schools and other activities. B-IGSM s PhD researchers are coached and advised by scientists both of the Technical University of Braunschweig and PTB. To support developing and emerging countries to participate in the programme the German Federal Ministry for Economic Cooperation and Development (BMZ) provides funding for two students of its partner countries engaged in natural sciences or engineering (please see list of partner countries). Initial funding will be granted for one year. Given that it typically takes three years to complete a doctoral thesis PTB will be committed to obtain a follow-up funding. The size of the grants is comparable to grants provided by the German Academic Exchange Service (DAAD). The positions will be located at. An excellent academic record and fluent English are prerequisites; skills in the German language are welcome. The submission should include CV, transcripts of the most important documents of professional qualification and a letter of application. Candidates affiliated to a national metrology institute or a designated institute will be highly encouraged to apply. B- IGSM promotes the professional equality of women and men and is thus especially interested in applications from women. Disabled persons will be given priority if they have the same occupational aptitude. Any granting of a scholarship has to be approved by the International Office of taking into account the Promotionsordnung (PhD Regulations) of the respective faculty where the scholarship will be located. Applications need to be submitted via the application portal of B-IGSM: Deadline for application is February, 28th 2017.

2 Applications can be submitted for the following topics: 1. Construction and Characterization of a Reference Spectrometer for Calibration of Reference Impedances in mohm Range Impedance spectrometers are now increasingly used for the metrological characterization of High energy Li-ion batteries. Battery storage systems are important parts for electric mobility and Energiewende. The electrochemical working group of PTB has developed a reference measurement setup to derive empirical parameters from electrochemical impedance spectra of Li-ion battery cells that are sensitive to aging of Li-ion battery cells. The Institute for High Voltage and Electrical Power Systems of the examines at the Battery LabFactory Braunschweig (BLB) the influence of formation on cell performance and develops analytical methods for determination of quality indicators. To derive the cell performance, the cell is aged cyclic and calendrically at different conditions while the SOH (State of Health) is continuously monitored. At PTB the SOH is determined according to a specially developed method of electrochemical impedance spectra. As part of the PhD project the PHD student at PTB builds a measuring station. This station should be able to measure AC current, AC voltage and their respective phase position independently at impedances in the mω range. The spectrometer has to be characterized in terms of stability, repeatability and measurement error. This measuring station also has to be able to be used as a calibration reference for impedances, which in turn are used for calibrating impedance spectrometers. The spectrometer is intended to enable the return of the measured impedance spectra, for SOH determination, to the International System of Units. Applicants should have a master or comparable degree in physics, chemistry or engineering and basic experience in power electronics. Prof. Dr. Michael Kurrat Institute for High Voltage and Electrical Power Systems m.kurrat@tu-braunschweig.de 2. Fluorescence Enhancement for Point-of-Care Diagnostics We develop nanotechnological devices that act as fluorescence amplifiers in biosensing and diagnostics. Using self-assembled plasmonic structures we enhance the fluorescence more than 1000fold enabling direct single-molecule detection on low-tec devices that can be used at the point-of-need. The plasmonic structures are produced in a cost-efficient way by DNA nanotechnology. In the context of this project, the metrological characterization of this technology with respect to homogeneity and reproducibility will be the focus. Finally, we aim at detecting single molecules on devices as simple as a modified smartphone. Prof. Dr. Philip Tinnefeld Institut für Physikalische und Theoretische Chemie p.tinnefeld@tu-braunschweig.de

3 3. Influence of Temperature in Additive Manufacturing Additive manufacturing is getting more and more influence in many production processes. Not only polymers are processed, but metals and ceramics are gaining in importance. The quality of all manufactured objects is influenced by temperature. This regards the temperature of the nozzle during printing, the temperature of the heat bed, the homogeneity of temperature with in the printer enclosure and many more influencing parameters. In this PhD thesis the influence of temperature should be investigated in a systematic study and the most important influences of temperature on the final dimensional tolerances of the products will be analysed. The methods for temperature measurement have to be adapted to the processed material. To determine without contact the nozzle temperature radiation thermometry can be engaged. The heat bed homogeneity is investigated by thermal imaging. For the temperature control different contact thermometers are employed. For optimization of novel polymers in additive manufacturing the glass temperature, the melting point and the temperature dependence of viscosity and of the elastic properties have to be investigated. All these temperature measurement should fit into a consistent picture with well understood measurement uncertainties. Prof. Dr. Meinhard Schilling Institut für Elektrische Messtechnik und Grundlagen der Elektrotechnik m.schilling@tu-braunschweig.de 4. Integrated Wearable Biophotonic Sensor Systems for Point-Of-Care Medical Diagnosis The development of novel sensor systems for Point-of-Care medical diagnosis has been becoming an active new area of nano-optoelectronics. In particular the integration of nanoscale optical devices (e.g., nano-light-emitting diodes (nanoleds) or laser diodes in the UV spectral range) opens up many new possibilities for biophotonics. Wearable, multifunctional sensor technology would be highly desirable in many cases such as ambulatory monitoring and disorder observation in both clinical and home use. The aim of this project is to develop highly integrated, wearable optical sensing systems integrated with blood oxygen saturation, blood pressure or other measurements by using LEDs. This nonintrusive, non-invasive, robust and low-cost diagnostic tool can continuously deliver us information of our body condition, which will be further used as a basis for continuous ambulatory health monitoring. As will become clear below, the measurement techniques for various health monitors (e.g., blood pressure and blood sugar levels) in a human depend on many cross-correlations and will be influenced by many parameters, which are not directly related to the measurement itself. Assessing the measurement uncertainties to evaluate the reliability of health monitoring data on the basis of a full metrological analysis therefore is a major ingredient of future pointof-care medical technology. Therefore, besides the development of optical health monitoring systems (i.e., including both hardware and software), the metrological aspects of health monitoring will be a major focus of this project. Novel monitoring systems will not only be

4 developed, but also their measurement uncertainties will be determined quantitatively in order to build trustable health monitoring systems. The Institute of Semiconductor Technology (IHT) at Technische Universität Braunschweig operates strong research programs on GaN optoelectronics and nanoelectronics, including GaN epitaxy, material analysis, LED development and optoelectronic systems, in close collaboration with industrial partners. The project will be embedded in the excellent research environment at IHT, including the epitaxy competence center (ec2), operated in close collaboration with Osram Opto Semiconductors GmbH, as well as the Laboratroy of Emerging Nanometrology (LENA), a research center devoted to the development of nanometrology, in close collaboration with our core partner Physikalisch-Technische Bundesanstalt (PTB) Braunschweig. Prof. Dr. Andreas Waag Institute for Semiconductor Technology a.waag@tu-braunschweig.de 5. Metrological Optimization of Nonlinear Frequency Response Analysis High energy Li-ion batteries are most important energy storage devices for electric traction within the foreseeable future. The Institute of Energy and Process Systems Engineering of the has applied Nonlinear Frequency Responses Analysis (NFRA) to Lithium- Ion-Batteries to characterize the properties and dynamics of the battery. In comparison to the established and common dynamic measurement method of Electrochemical Impedance Spectroscopy (EIS) higher AC excitation current amplitudes can be accessed with NFRA. EIS allows dynamic analysis only under the assumption of a linear response to the excitation, therefore nonlinear electrochemcial and physical processes in the battery are simplified. NFRA extends dynamic analysis to the nonlinear domain. Additionally to the linear response, higher harmonic voltage responses are analyzed in the frequency domain. The PhD student should advance our NRFA measurement procedure experimentally. For this purpose, optimal measurements conditions must be determined and measurement results must be characterized with respect to common metrological issues like traceability, reproducibility and measurement uncertainty, etc. Special focus must be placed on identifying and considering artifacts in the metrological assessment that occur due to measurement signal conditioning of the device. Such a conditioning is needed to optimize the design of an instrument for processing NFRA on batteries. Development of a deep understanding of the measurement technique under metrological aspects is essential to complete the task. Applicants should have a master or comparable degree in physics, engineering or electrical technology and basic experience in laboratory work. Prof. Dr. Ulrike Krewer Institute of Energy and Process Systems Engineering u.krewer@tu-braunschweig.de

5 6. Metrology of EMI Radio Receiving Properties Radio interference due to non-intended signals at a receiver s input is a long and well known phenomenon. Interference is sometimes dealt with in the simplest possible way: Some EMI standards specify thresholds for non-intended signals, e.g. maximal disturbing field strengths at the receiver s antenna, by not exceeding the receiver s input noise floor data. If more realistic scenarios are of interest, a lot of parameters come into play both of the intended as well as the unintended signal and their corresponding ratios, e.g. their absolute values, spectral frequency content and time behavior, etc. Not much has been done to characterize such interference scenarios in a quantitative way. Further this has to include the individual properties of the receiver system since its nonlinearities and signal processing stages have a fundamental influence on interference characteristics, too. Newest arbitrary waveform generators (AWG) with highest sample rates and flexible signal generation/programming make it possible to analyze such scenarios in a quantitative way (a first approach is documented in Investigating EMI-characteristics of navigation receivers ; R.Geise et al, ESA workshop on Aerospace EMC, Valencia/Spain 2016). The proposed PhD thesis shall systematize such analysis. Prof. Dr. Achim Enders Institute for Electromagnetic Compatibility achim.enders@tu-braunschweig.de