TY - JOUR A1 - Guo, Yuanyuan A1 - Miyamoto, Ko-ichiro A1 - Wagner, Torsten A1 - Schöning, Michael Josef A1 - Yoshinobu, Tatsuo T1 - Device simulation of the light-addressable potentiometric sensor for the investigation of the spatial resolution JF - Sensors and actuators B: Chemical N2 - As a semiconductor-based electrochemical sensor, the light-addressable potentiometric sensor (LAPS) can realize two dimensional visualization of (bio-)chemical reactions at the sensor surface addressed by localized illumination. Thanks to this imaging capability, various applications in biochemical and biomedical fields are expected, for which the spatial resolution is critically significant. In this study, therefore, the spatial resolution of the LAPS was investigated in detail based on the device simulation. By calculating the spatiotemporal change of the distributions of electrons and holes inside the semiconductor layer in response to a modulated illumination, the photocurrent response as well as the spatial resolution was obtained as a function of various parameters such as the thickness of the Si substrate, the doping concentration, the wavelength and the intensity of illumination. The simulation results verified that both thinning the semiconductor substrate and increasing the doping concentration could improve the spatial resolution, which were in good agreement with known experimental results and theoretical analysis. More importantly, new findings of interests were also obtained. As for the dependence on the wavelength of illumination, it was found that the known dependence was not always the case. When the Si substrate was thick, a longer wavelength resulted in a higher spatial resolution which was known by experiments. When the Si substrate was thin, however, a longer wavelength of light resulted in a lower spatial resolution. This finding was explained as an effect of raised concentration of carriers, which reduced the thickness of the space charge region. The device simulation was found to be helpful to understand the relationship between the spatial resolution and device parameters, to understand the physics behind it, and to optimize the device structure and measurement conditions for realizing higher performance of chemical imaging systems. Y1 - 2014 U6 - https://doi.org/10.1016/j.snb.2014.08.016 SN - 1873-3077 (E-Journal); 0925-4005 (Print) VL - 204 SP - 659 EP - 665 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Reisert, Steffen A1 - Geissler, H. A1 - Weiler, C. A1 - Wagner, P. A1 - Schöning, Michael Josef T1 - Multiple sensor-type system for monitoring the microbicidal effectiveness of aseptic sterilisation processes JF - Food control N2 - The present work describes a novel multiple sensor-type system for the real-time analysis of aseptic sterilisation processes employing gaseous hydrogen peroxide (H2O2) as a sterilant. The inactivation kinetics of Bacillus atrophaeus by gaseous H2O2 have been investigated by means of a methodical calibration experiment, taking into account the process variables H2O2 concentration, humidity and gas temperature. It has been found that the microbicidal effectiveness at H2O2 concentrations above 2% v/v is largely determined by the concentration itself, while at lower H2O2 concentrations, the gas temperature and humidity play a leading role. Furthermore, the responses of different types of gas sensors towards the influencing factors of the sterilisation process have been analysed within the same experiment. Based on a correlation established between the inactivation kinetics and the sensor responses, a calorimetric H2O2 sensor and a metal-oxide semiconductor (MOX) sensor have been identified as possible candidates for monitoring the microbicidal effectiveness of aseptic sterilisation processes employing gaseous H2O2. Therefore, two linear models that describe the relationship between sensor response and microbicidal effectiveness have been proposed. Y1 - 2015 U6 - https://doi.org/10.1016/j.foodcont.2014.07.063 SN - 1873-7129 (E-Journal); 0956-7135 (Print) VL - 47 SP - 615 EP - 622 ER - TY - JOUR A1 - Khaydukova, M. M. A1 - Zadorozhnaya, O. A. A1 - Kirsanov, D. O. A1 - Iken, Heiko A1 - Rolka, David A1 - Schöning, Michael Josef A1 - Babain, V. A. A1 - Vlasov, Yu. G. A1 - Legin, A. V. T1 - Multivariate processing of atomic-force microscopy images for detection of the response of plasticized polymeric membranes JF - Russian journal of applied chemistry N2 - The possibility of using the atomic-force microscopy as a method for detection of the analytical signal from plasticized polymeric sensor membranes was analyzed. The surfaces of cadmium-selective membranes based on two polymeric matrices were examined. The digital images were processed with multivariate image analysis techniques. A correlation was found between the surface profile of an ion-selective membrane and the concentration of the ion in solution. Y1 - 2014 U6 - https://doi.org/10.1134/S1070427214030112 SN - 1608-3296 (E-Journal); 1070-4272 (Print) VL - 87 IS - 3 SP - 307 EP - 314 PB - Springer CY - Dordrecht ER - TY - CHAP A1 - Schirra, Julian A1 - Watmuff, Jon A1 - Bauschat, J.-Michael T1 - A relative assessment of existing potential-methodologies to accurately estimate the induced drag of highly non-planar lifting systems T2 - Advanced aero concepts, design and operations : Applied Aerodynamics Conference : July 22 -24, 2014, Bristol, UK Y1 - 2014 SP - 1 EP - 13 ER - TY - CHAP A1 - Wetter, Martin A1 - Kern, Alexander T1 - Number of lightning strikes to tall structures - comparison of calculations and measurements using a modern lightning monitoring system T2 - 2014 International Conference on Lightning Protection (ICLP), Shanghai, China Y1 - 2014 SP - 1 EP - 7 ER - TY - CHAP A1 - Kern, Alexander A1 - Schelthoff, Christof A1 - Mathieu, Moritz T1 - Calculation of interception efficiencies for mesh-type air-terminations according to IEC 62305-3 using a dynamic electro-geometrical model T2 - International Conference on Lightning Protection (ICLP) : 2 - 7 Sept. 2012, Vienna Y1 - 2012 SN - 978-1-4673-1896-9 (E-Book) ; 978-1-4673-1898-3 (Print) SP - 1 EP - 6 PB - IEEE CY - Piscataway, NJ ER - TY - CHAP A1 - Lo Piparo, G. B. A1 - Kern, Alexander A1 - Mazzetti, C. T1 - Some masterpoints about risk due to lightning T2 - International Conference on Lightning Protection (ICLP) : 2 - 7 Sept. 2012, Vienna Y1 - 2012 SN - 978-1-4673-1896-9 (E-Book) ; 978-1-4673-1898-3 (Print) SP - 1 EP - 6 PB - IEEE CY - Piscataway, NJ ER - TY - JOUR A1 - Müller, Martin A1 - Hirschfeld, Julian A1 - Lambertz, Rita A1 - Schulze Lohoff, Andreas A1 - Lustfeld, Hans A1 - Pfeifer, Heinz A1 - Reißel, Martin T1 - Validation of a novel method for detecting and stabilizing malfunctioning areas in fuel cell stacks JF - Journal of power sources N2 - In this paper a setup for detecting malfunctioning areas of MEAs in fuel cell stacks is described. Malfunctioning areas generate electric cross currents inside bipolar plates. To exploit this we suggest bipolar plates consisting not of two but of three layers. The third one is a highly conducting layer and segmented such that the cross currents move along the segments to the surface of the stack where they can be measured by an inductive sensor. With this information a realistic model can be used to detect the malfunctioning area. Furthermore the third layer will prevent any current inhomogeneity of a malfunctioning cell to spread to neighbouring cells in the stack. In this work the results of measurements in a realistic cell setup will be compared with the results obtained in simulation studies with the same configuration. The basis for the comparison is the reliable characterisation of the electrical properties of the cell components and the implication of these results into the simulation model. The experimental studies will also show the limits in the maximum number of segments, which can be used for a reliable detection of cross currents. Y1 - 2014 U6 - https://doi.org/10.1016/j.jpowsour.2014.08.045 SN - 1873-2755 (E-Journal); 0378-7753 (Print) VL - 272 SP - 225 EP - 232 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Stadler, Alexander Maximilian A1 - Garvey, Christopher J. A1 - Embs, Jan Peter A1 - Koza, Michael Marek A1 - Unruh, Tobias A1 - Artmann, Gerhard A1 - Zaccai, Guiseppe T1 - Picosecond dynamics in haemoglobin from different species: A quasielastic neutron scattering study JF - Biochimica et biophysica acta (BBA): General Subjects Y1 - 2014 U6 - https://doi.org/10.1016/j.bbagen.2014.06.007 SN - 1872-8006 (E-Journal); 0304-4165 (Print) VL - 1840 IS - 10 SP - 2989 EP - 2999 PB - Elsevier CY - Amsterdam ER - TY - PAT A1 - Bessler, Cornelius A1 - Maurer, Karl-Heinz A1 - Merkel, Marion A1 - Siegert, Petra A1 - Wieland, Susanne T1 - Subtilisin from Bacillus Pumilus and detergent and cleaning agents containing said novel subtilisin [US Patentanmeldung / Internationale Patentanmeldung] Y1 - 2009 SP - 1 EP - 39 PB - USPTO; WIPO CY - Washington; Genf ER - TY - CHAP A1 - Pfaff, Raphael A1 - Burnham, Keith J. T1 - On abstraction and interpretability: a behavioural perspective T2 - 19th International Conference on Systems Engineering 2008 : ICSENG '08 : 19 - 21 Aug. 2008, University of Nevada, Las Vegas, Nevada Y1 - 2008 SN - 978-0-7695-3331-5 ; 978-0-7695-2719-2 SP - 89 EP - 94 PB - IEEE CY - Piscataway, NJ ER - TY - JOUR A1 - Pfaff, Raphael A1 - Burnham, Keith J. T1 - On abstraction and interpretability: a behavioural perspective JF - Systems Science Y1 - 2009 SN - 0137-1223 VL - Vol. 35 IS - Iss. 2 SP - 19 EP - 26 ER - TY - JOUR A1 - Seiler, Friedrich A1 - Pichler, Alexander A1 - Pfaff, Raphael A1 - Srulijes, Julio T1 - Novel processing tools for automated doppler picture velocimetry (DPV) evaluation JF - Journal of visualization Y1 - 2009 SN - 1343-8875 VL - Vol. 12 IS - Iss. 4 SP - 323 EP - 337 ER - TY - JOUR A1 - Yoshinobu, Tatsuo A1 - Miyamoto, Ko-ichiro A1 - Wagner, Torsten A1 - Schöning, Michael Josef T1 - Recent developments of chemical imaging sensor systems based on the principle of the light-addressable potentiometric sensor JF - Sensors and actuators B: Chemical N2 - The light-addressable potentiometric sensor (LAPS) is an electrochemical sensor with a field-effect structure to detect the variation of the Nernst potential at its sensor surface, the measured area on which is defined by illumination. Thanks to this light-addressability, the LAPS can be applied to chemical imaging sensor systems, which can visualize the two-dimensional distribution of a particular target ion on the sensor surface. Chemical imaging sensor systems are expected to be useful for analysis of reaction and diffusion in various electrochemical and biological samples. Recent developments of LAPS-based chemical imaging sensor systems, in terms of the spatial resolution, measurement speed, image quality, miniaturization and integration with microfluidic devices, are summarized and discussed. Y1 - 2015 U6 - https://doi.org/10.1016/j.snb.2014.09.002 SN - 1873-3077 (E-Journal); 0925-4005 (Print) VL - 207, Part B SP - 926 EP - 932 PB - Elsevier CY - Amsterdam ER - TY - THES A1 - Pfaff, Raphael T1 - Evaluation and extension of the potential for application of the behavioural framework to practical engineering problems Y1 - 2013 N1 - Coventry, Univ., Diss., 2013 ER - TY - THES A1 - Pfaff, Raphael T1 - Automated processing of the ISL Doppler images Y1 - 2007 N1 - Hagen, Fernuniv., Bachelorarbeit, 2007 ER - TY - THES A1 - Pfaff, Raphael T1 - Modelling of nonlinear systems using piecewise defined models Y1 - 2006 N1 - Coventry, Univ., Masterarbeit, 2006 ER - TY - CHAP A1 - Pfaff, Raphael A1 - Larkowski, Tomasz A1 - Burnham, Keith J. T1 - An application of adaptive control in the behavioural framework T2 - 21st International Conference on Systems Engineering (ICSEng) : 16 - 18 Aug. 2011, Las Vegas, Nevada ; proceedings Y1 - 2011 SN - 978-1-4577-1078-0 ; 978-0-7695-4495-3 SP - 49 EP - 54 PB - IEEE CY - Piscataway, NJ ER - TY - CHAP A1 - Pfaff, Raphael A1 - Larkowski, Tomasz A1 - Burnham, Keith J. T1 - An approach to adaptive control in the behavioural framework T2 - UKACC International Conference on Control 2010 (CONTROL 2010) : Coventry, United Kingdom, 7 - 10 September 2010 ; Vol. 2. (IET seminar digest ; 2010/004) Y1 - 2010 SN - 978-1-62748-119-9 SP - 833 EP - 838 PB - Curran CY - Red Hook, NY ER - TY - CHAP A1 - Seiler, Friedrich A1 - Pichler, Alexander A1 - Pfaff, Raphael A1 - George, Alfred A1 - Srulijes, Julio T1 - Improved Doppler picture velocimetry and new automated processing T2 - 14th International Symposium on Applications of Laser Techniques to Fluid Mechanics : Lisbon, Portugal, 7 - 10 July 2008 Y1 - 2008 SP - 1 EP - 12 ER -