TY  - JOUR
A1  - Lustfeld, Hans
A1  - Hirschfeld, Julian A.
A1  - Reißel, Martin
A1  - Steffen, Bernhard
T1  - Enhancement of precision and reduction of measuring points in tomographic reconstructions
JF  - Physics Letters A
Y1  - 2011
SN  - 0375-9601
VL  - 375
IS  - 8
SP  - 1167
EP  - 1171
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Hirschfeld, Julian A.
A1  - Lustfeld, Hans
A1  - Reißel, Martin
A1  - Steffen, Bernhard
T1  - A novel scheme for precise diagnostics and effective stabilization of currents in a fuel cell stack
JF  - International Journal of Energy Research
N2  - A novel scheme for detecting inhomogeneous internal currents in a fuel cell stack is presented. In this paper the scheme is investigated for the case that the flow field plates consist of graphite. Then plates of high conductivity, e.g. aluminium between the flow field plates together with small slits in these plates have three effects: (a) Whenever a local inhomogeneity of the electric current occurs at a particular cell in the stack, this will induce a surface current close to that cell perpendicular to the averaged current. This current can be detected. (b) The plates of high conductivity completely prevent the inhomogeneities from spreading to neighbouring cells. (c) Even at the particular cell the inhomogeneity is suppressed as far as possible. Thus this scheme leads to much better diagnostic possibilities and at the same time reduces electric instabilities to an extent, where they probably become harmless. This scheme will first be explained for a simple model to clarify the idea. However, very precise three dimensional computations using realistic parameters are presented, corroborating the results of the simple model.
Y1  - 2010
U6  - https://doi.org/10.1002/er.1662
SN  - 0363-907X
VL  - 34
IS  - 3
SP  - 293
EP  - 301
PB  - Wiley
CY  - London
ER  - 
TY  - JOUR
A1  - Hirschfeld, Julian A.
A1  - Lustfeld, Hans
A1  - Reißel, Martin
A1  - Steffen, Bernhard
T1  - Tomographic diagnostics of current distributions in a fuel cell stack
JF  - International Journal of Energy Research
N2  - A novel tomographic scheme for analysing the state of any single membrane electrode assembly (MEA) in a stack is suggested. Plates of very high conductivity placed between every fuel cell and slitted in an appropriate manner cause surface currents at well-defined locations of the stack. We show that knowing these surface currents, information about anomalies of the currents in a MEA can be obtained using the methods of tomography. The results are mathematically not unique. However, when assuming plausible defect structures, one can exclude improbable deficiencies by applying a special form of simulated annealing. We present numerical calculations of typical examples demonstrating that the essential defects of the MEA in any single cell of the stack can be detected and their extent can be determined.
Y1  - 2010
U6  - https://doi.org/10.1002/er.1634
SN  - 0363-907X
VL  - 34
IS  - 3
SP  - 284
EP  - 292
PB  - Wiley
CY  - London
ER  - 
TY  - JOUR
A1  - Reisert, Steffen
A1  - Henkel, H.
A1  - Schneider, A.
A1  - Schäfer, Daniel
A1  - Friedrich, P.
A1  - Berger, Jörg
A1  - Schöning, Michael Josef
T1  - Entwicklung eines Handheld-Sensorsystems für die „On-line“-Messung der H2O2-Konzentration in aseptischen Entkeimungsprozessen
JF  - 9. Dresdner Sensor-Symposium : Dresden, 07.-09. Dezember 2009 / Gerlach, Gerald ; Hauptmann, Peter [Hrsg.]
Y1  - 2009
SN  - 978-3-941298-44-6
N1  - Dresdner Sensor-Symposium ; (9, 2009, Dresden)
SP  - 285
EP  - 288
PB  - TUDpress
CY  - Dresden
ER  - 
TY  - JOUR
A1  - Reißel, Martin
A1  - Lustfeld, Hans
A1  - Hirschfeld, Julian A.
A1  - Steffen, Bernhard
T1  - Uniqueness of magnetotomography for fuel cells and fuel cell stacks / Lustfeld, H. ; Hirschfeld, J. ; Reißel, M ; Steffen, B.
JF  - Journal of Physics A: Mathematical and Theoretical. 42 (2009), H.  495205
Y1  - 2009
SN  - 0022-3689
SP  - 9 S.
ER  - 
TY  - JOUR
A1  - Reißel, Martin
A1  - Hirschfeld, Julian A.
A1  - Lustfeld, Hans
A1  - Steffen, Bernhard
T1  - Magnetotomography and Electric Currents in a Fuel Cell / Lustfeld, H. ; Reißel, M. ; Steffen, B.
JF  - Fuel Cells. 9 (2009), H. 4
Y1  - 2009
SN  - 1615-6854
SP  - 474
EP  - 481
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Schöning, Michael Josef
A1  - Yoshinobu, T.
A1  - Schubert, J.
A1  - Steffen, A.
A1  - Lüth, H.
T1  - Innovative Schichttechniken und Messprinzipien für kapazitive Feldeffektsensoren
JF  - Sensoren und Mess-Systeme : Vorträge der 11. ITG/GMA-Fachtagung vom 11. bis 12. März 2002 in Ludwigsburg / Veranst.: Informationstechnische Gesellschaft im VDE (ITG) ... Wiss. Tagungsleitung: C. D. Kohl ....
Y1  - 2002
SN  - 3-8007-2675-0
N1  - Sensoren und Mess-Systeme 2002
SP  - 151
EP  - 154
PB  - VDE-Verl.
CY  - Berlin [u.a.]
ER  - 
TY  - JOUR
A1  - Poghossian, Arshak
A1  - Thust, M.
A1  - Schroth, P.
A1  - Steffen, A.
A1  - Lüth, H.
A1  - Schöning, Michael Josef
T1  - Penicillin detection by means of silicon-based field-effect structures
JF  - Sensors and Materials. 13 (2001), H. 4
Y1  - 2001
SN  - 0392-2510
SP  - 207
EP  - 223
ER  - 
TY  - JOUR
A1  - Schöning, Michael Josef
A1  - Malkoc, Ü.
A1  - Thust, M.
A1  - Steffen, A.
A1  - Kordos, P.
A1  - Lüth, H.
T1  - Novel electrochemical sensors with structured and porous semiconductor/insulator capacitors
JF  - Sensors and Actuators B. 65 (2000), H. 1-3
Y1  - 2000
SN  - 0925-4005
SP  - 288
EP  - 290
ER  - 
TY  - JOUR
A1  - Lüth, H.
A1  - Thust, M.
A1  - Steffen, A.
A1  - Kordos, P.
A1  - Schöning, Michael Josef
T1  - Biochemical sensors with structured and porous silicon capacitors
JF  - Materials Science and Engineering B. 69-70 (2000)
Y1  - 2000
SN  - 0921-5107
SP  - 104
EP  - 108
ER  -