TY  - JOUR
A1  - Tippkötter, Nils
A1  - Deterding, A.
A1  - Ulber, Roland
T1  - Determination of acetic acid in fermentation broth by gas-diffusion technique
JF  - Engineering in Life Sciences
N2  - Due to the interfering effects of acetic acid in many fermentation processes, a gas-diffusion technique was developed for the online determination of acetic acid. The measurements were accomplished with a flow diffusion analysis (FDA) unit from the TRACE Analytics GmbH, Braunschweig, Germany. The diffusion analysis is based on the UV-absorbance of acetic acid at 205 nm. The measurement was achieved by the separation of an acceptor and a carrier stream (acidified fermentation broth) using a gas permeable polytetrafluoroethylene (PTFE) membrane, whereby broth constituents that would otherwise disturb the UV-measurement of acetic acid, are held back efficiently. Merely, the fermentation by-products, e.g. formic acid, is capable of diffusing through the membrane. While formic acid can disturb the measurement, carbon dioxide does not absorb at 205 nm. The method operates with time-dependent sample enrichment. During the analysis, a small volume of the acceptor stream is stopped for a defined time interval in the acceptor chamber. During this period, the gaseous acetic acid diffuses through the membrane and is enriched in the acceptor chamber. Subsequently after the enrichment, the acceptor stream flows through a UV-detector. The intensity of the signal is proportional to the acetic acid concentration. Online measurements in bioreactors via a sterile filtration probe have been accomplished. A linear calibration in the range of 0.5–5.0 g/L acetic acid with a relative standard deviation of <5 % was obtained. A sampling rate of 8 samples per hour was possible. The system was applied for the determination of acetic acid in E. coli fermentation broth. The instrument is easy to clean, very user-friendly and does not require any toxic or expensive reagents.
Y1  - 2008
U6  - https://doi.org/10.1002/elsc.200820227
VL  - 8
IS  - 1, Special Issue: Technical Systems for the Use in Life Sciences
SP  - 62
EP  - 67
ER  - 
TY  - CHAP
A1  - Schuh, Günther
A1  - Gottschalk, Sebastian
A1  - Höhne, Tim
A1  - Attig, Philipp
ED  - Mitsuishi, M.
T1  - Further Potentials of Smart Logistics
T2  - Manufacturing Systems and Technologies for the New Frontier
Y1  - 2008
SN  - 978-1-84800-267-8
SN  - 978-1-84800-266-1 (Printausgabe)
U6  - https://doi.org/10.1007/978-1-84800-267-8_18
N1  - The 41St Cirp Conference On Manufacturing Systems, May 26-28, 2008, Tokyo, Japan
SP  - 93
EP  - 96
PB  - Springer
CY  - London
ER  - 
TY  - CHAP
A1  - Tippkötter, Nils
A1  - Roikaew, W.
A1  - Ulber, Roland
T1  - An automated pilot plant for the bioengineering processing of concentrated whey
T2  - European BioPerspectives : in cooperation with BIOTECHNICA 2008 : 7 - 9 October 2008 Hannover, Germany ; book of abstracts ; abstracts, poster programme
Y1  - 2008
SP  - 98
PB  - Dechema
CY  - Frankfurt am Main
ER  - 
TY  - BOOK
A1  - Drumm, Christian
T1  - Improving Schema Mapping by Exploiting Domain Knowledge
Y1  - 2008
N1  - Karlsruhe, Univ., Diss., 2008
ER  - 
TY  - BOOK
A1  - Moosdorf, Andreas
T1  - The determinants of international knowledge transfer effectiveness - conceptual advances and empirical verification
Y1  - 2008
N1  - The University of Leeds > Leeds University Business School. Thesis (PhD)
ER  - 
TY  - THES
A1  - Tran, Thanh Ngoc
T1  - Limit and shakedown analysis of plates and shells including uncertainties
Y1  - 2008
N1  - Chemnitz, Techn. Univ., Diss., 2008
ER  - 
TY  - JOUR
A1  - Tippkötter, Nils
A1  - Roikaew, W.
A1  - Ulber, Roland
T1  - Nitrate removal from whey concentrate with biotechnological regeneration of the waste water
JF  - European dairy magazine : EDM
Y1  - 2008
SN  - 0936-6318
IS  - 1
SP  - 30
EP  - 32
ER  - 
TY  - JOUR
A1  - Lerchl, Alexander
A1  - Krüger, Heike
A1  - Niehaus, Michael
A1  - Streckert, Joachim R.
A1  - Bitz, Andreas
A1  - Hansen, Volkert
T1  - Effects of mobile phone electromagnetic fields at nonthermal SAR values on melatonin and body weight of Djungarian hamsters (Phodopus sungorus)
JF  - Journal of Pineal Research
Y1  - 2008
U6  - https://doi.org/10.1111/j.1600-079X.2007.00522.x
SN  - 1600-079X
VL  - 44
IS  - 3
SP  - 267
EP  - 272
ER  - 
TY  - CHAP
A1  - Osterhage, Hannes
A1  - Bialonski, Stephan
A1  - Staniek, Matthäus
A1  - Schindler, Kaspar
A1  - Wagner, Tobias
A1  - Elger, Christian E.
A1  - Lehnertz, Klaus
T1  - Bivariate and multivariate time series analysis techniques and their potential impact for seizure prediction
T2  - Seizure Prediction in Epilepsy: From Basic Mechanisms to Clinical Applications
Y1  - 2008
SN  - 978-3-527-62519-2
U6  - https://doi.org/10.1002/9783527625192.ch15
SP  - 189
EP  - 208
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Schindler, Kaspar A.
A1  - Bialonski, Stephan
A1  - Horstmann, Marie-Therese
A1  - Elger, Christian E.
A1  - Lehnertz, Klaus
T1  - Evolving functional network properties and synchronizability during human epileptic seizures
JF  - Chaos: An Interdisciplinary Journal of Nonlinear Science
Y1  - 2008
U6  - https://doi.org/10.1063/1.2966112
SN  - 1089-7682
VL  - 18
IS  - 3
SP  - 033119
ER  -