TY  - JOUR
A1  - Jildeh, Zaid B.
A1  - Kirchner, Patrick
A1  - Baltes, Klaus
A1  - Wagner, Patrick H.
A1  - Schöning, Michael Josef
T1  - Development of an in-line evaporation unit for the production of gas mixtures containing hydrogen peroxide – numerical modeling and experimental results
JF  - International Journal of Heat and Mass Transfer
N2  - Hydrogen peroxide (H2O2) is a typical surface sterilization agent for packaging materials used in the pharmaceutical, food and beverage industries. We use the finite-elements method to analyze the conceptual design of an in-line thermal evaporation unit to produce a heated gas mixture of air and evaporated H2O2 solution. For the numerical model, the required phase-transition variables of pure H2O2  solution and of the aerosol mixture are acquired from vapor-liquid equilibrium (VLE) diagrams derived from vapor-pressure formulations. This work combines homogeneous single-phase turbulent flow with heat-transfer physics to describe the operation of the evaporation unit. We introduce the apparent heat-capacity concept to approximate the non-isothermal phase-transition process of the H2O2-containing aerosol. Empirical and analytical functions are defined to represent the temperature- and pressure-dependent material properties of the aqueous H2O2 solution, the aerosol and the gas mixture. To validate the numerical model, the simulation results are compared to experimental data on the heating power required to produce the gas mixture. This shows good agreement with the deviations below 10%. Experimental observations on the formation of deposits due to the evaporation of stabilized H2O2 solution fits the prediction made from simulation results.
Y1  - 2019
U6  - https://doi.org/10.1016/j.ijheatmasstransfer.2019.118519
SN  - 0017-9310
VL  - 143
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Iken, Heiko
A1  - Bronder, Thomas
A1  - Goretzki, Alexander
A1  - Kriesel, Jana
A1  - Ahlborn, Kristina
A1  - Gerlach, Frank
A1  - Vonau, Winfried
A1  - Zander, Willi
A1  - Schubert, Jürgen
A1  - Schöning, Michael Josef
T1  - Development of a Combined pH- and Redox-Sensitive Bi-Electrode Glass Thin-Film Sensor
JF  - physica status solidi a : applications and materials sciences
Y1  - 2019
U6  - https://doi.org/10.1002/pssa.201900114
SN  - 1862-6319
VL  - 216
IS  - 12
SP  - 1
EP  - 8
PB  - Wiley
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Arreola, Julio
A1  - Keusgen, Michael
A1  - Wagner, Torsten
A1  - Schöning, Michael Josef
T1  - Combined calorimetric gas- and spore-based biosensor array for online monitoring and sterility assurance of gaseous hydrogen peroxide in aseptic filling machines
JF  - Biosensors and Bioelectronics
Y1  - 2019
U6  - https://doi.org/10.1016/j.bios.2019.111628
SN  - 0956-5663
VL  - 143
IS  - 111628
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Dantism, Shahriar
A1  - Röhlen, Desiree
A1  - Wagner, Torsten
A1  - Wagner, P.
A1  - Schöning, Michael Josef
T1  - A LAPS-based differential sensor for parallelized metabolism monitoring of various bacteria
JF  - Sensors
N2  - Monitoring the cellular metabolism of bacteria in (bio)fermentation processes is crucial to control and steer them, and to prevent undesired disturbances linked to metabolically inactive microorganisms. In this context, cell-based biosensors can play an important role to improve the quality and increase the yield of such processes. This work describes the simultaneous analysis of the metabolic behavior of three different types of bacteria by means of a differential light-addressable potentiometric sensor (LAPS) set-up. The study includes Lactobacillus brevis, Corynebacterium glutamicum, and Escherichia coli, which are often applied in fermentation processes in bioreactors. Differential measurements were carried out to compensate undesirable influences such as sensor signal drift, and pH value variation during the measurements. Furthermore, calibration curves of the cellular metabolism were established as a function of the glucose concentration or cell number variation with all three model microorganisms. In this context, simultaneous (bio)sensing with the multi-organism LAPS-based set-up can open new possibilities for a cost-effective, rapid detection of the extracellular acidification of bacteria on a single sensor chip. It can be applied to evaluate the metabolic response of bacteria populations in a (bio)fermentation process, for instance, in the biogas fermentation process.
Y1  - 2019
U6  - https://doi.org/10.3390/s19214692
SN  - 1424-8220
VL  - 19
IS  - 21
PB  - MDPI
CY  - Basel
ER  -