@article{TippkoetterDeterdingUlber2008, author = {Tippk{\"o}tter, Nils and Deterding, A. and Ulber, Roland}, title = {Determination of acetic acid in fermentation broth by gas-diffusion technique}, series = {Engineering in Life Sciences}, volume = {8}, journal = {Engineering in Life Sciences}, number = {1, Special Issue: Technical Systems for the Use in Life Sciences}, doi = {10.1002/elsc.200820227}, pages = {62 -- 67}, year = {2008}, abstract = {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.}, language = {en} } @article{SchoeningPoghossian2008, author = {Sch{\"o}ning, Michael Josef and Poghossian, Arshak}, title = {Detection of charged macromolecules by means of field-effect devices (FEDs): possibilities and limitations}, series = {Electrochemical sensors, biosensors and their biomedical applications / ed. by Xueji Zhang ...}, journal = {Electrochemical sensors, biosensors and their biomedical applications / ed. by Xueji Zhang ...}, publisher = {Elsevier Acad. Press}, address = {Amsterdam}, isbn = {978-0-12-373738-0}, pages = {187 -- 212}, year = {2008}, language = {en} } @article{Pietsch2008, author = {Pietsch, Wolfram}, title = {Der IT-Produktkompass - Ein Instrument f{\"u}r die Analyse von Gesch{\"a}ftsmodellen und die strategiekonforme Positionierung von IT-Produkten}, series = {Industrialisierung des Software-Managements}, journal = {Industrialisierung des Software-Managements}, publisher = {Ges. f{\"u}r Informatik}, address = {Bonn}, isbn = {978-3-88579-233-8}, pages = {73 -- 88}, year = {2008}, language = {de} } @article{KrokerFaberTrinkletal.2008, author = {Kroker, J. and Faber, Christian and Trinkl, C. and Z{\"o}rner, W.}, title = {Der Garten bleibt - solares Heizen mit W{\"a}rmepumpe und Latentw{\"a}rmespeicher verzichtet auf großfl{\"a}chige Erdw{\"a}rmetauscher}, series = {Erneuerbare Energien : das Magazin. 18 (2008), H. 8}, journal = {Erneuerbare Energien : das Magazin. 18 (2008), H. 8}, issn = {1436-8773}, pages = {46 -- 49}, year = {2008}, language = {de} } @article{OlbertzReinartz2008, author = {Olbertz, Klaus and Reinartz, Oliver}, title = {Der Arbeitskampf im Ungleichgewicht: Rechtm{\"a}ßigkeit des Unterst{\"u}tzungsstreiks?}, series = {Betriebs-Berater: BB ; Recht, Wirtschaft, Steuern}, journal = {Betriebs-Berater: BB ; Recht, Wirtschaft, Steuern}, issn = {0340-7918}, pages = {814}, year = {2008}, language = {de} } @article{Hirschberg2008, author = {Hirschberg, Rainer}, title = {Decentral pumps in heating systems - a new hydraulic approac}, series = {1st International Rotating Equipment Conference - Pumps and Compressors, 9th Pump Users International Forum, 9. Internationales Pumpenanwenderforum, Final Report, D{\"u}sseldorf, DE, 28.-29. Oct, 2008}, journal = {1st International Rotating Equipment Conference - Pumps and Compressors, 9th Pump Users International Forum, 9. Internationales Pumpenanwenderforum, Final Report, D{\"u}sseldorf, DE, 28.-29. Oct, 2008}, publisher = {-}, pages = {1 -- 10}, year = {2008}, language = {en} } @article{StadlerEmbsDigeletal.2008, author = {Stadler, Andreas M. and Embs, Jan P. and Digel, Ilya and Artmann, Gerhard and Unruh, Tobias and B{\"u}ldt, Georg and Zaccai, Guiseppe}, title = {Cytoplasmic water and hydration layer dynamics in human red blood cells}, series = {Journal of the American Chemical Society. 50 (2008), H. 130}, journal = {Journal of the American Chemical Society. 50 (2008), H. 130}, isbn = {1520-5126}, pages = {16852 -- 16853}, year = {2008}, language = {en} } @article{Digel2008, author = {Digel, Ilya}, title = {Controlling microbial adhesion : a surface engineering approach}, series = {Bioengineering in Cell and Tissue Research / Artmann, Gerhard M. ; Chien, Shu (Eds.)}, journal = {Bioengineering in Cell and Tissue Research / Artmann, Gerhard M. ; Chien, Shu (Eds.)}, publisher = {Springer}, address = {Berlin [u.a.]}, isbn = {978-3-540-75408-4}, pages = {601 -- 625}, year = {2008}, language = {en} } @article{AlexopoulosBreitbachHoffschmidtetal.2008, author = {Alexopoulos, Spiros and Breitbach, Gerd and Hoffschmidt, Bernhard and Stobbe, P.}, title = {Computational fluid flow of porous resic ceramic filtering modules and optimization of the channel edge form geometry}, series = {Proceedings : April 14 - 18, 2008, Leipzig, Germany / hosted by VDI, Society for Chemical and Process Engineering . Vol 2}, journal = {Proceedings : April 14 - 18, 2008, Leipzig, Germany / hosted by VDI, Society for Chemical and Process Engineering . Vol 2}, publisher = {Filtech Exhibitions}, address = {Meerbusch}, pages = {300 -- 304}, year = {2008}, language = {en} } @article{BehbahaniWalugaArltetal.2008, author = {Behbahani, Mehdi and Waluga, C. and Arlt, S. and Behr, M. and Mottaghy, K.}, title = {Computational Analysis of Platelet Aggregation in a Taylor-Couette System}, series = {The International Journal of Artificial Organs. 31 (2008), H. 7}, journal = {The International Journal of Artificial Organs. 31 (2008), H. 7}, isbn = {0391-3988}, pages = {643}, year = {2008}, language = {en} }