@article{WeldenJablonskiWegeetal.2021, author = {Welden, Rene and Jablonski, Melanie and Wege, Christina and Keusgen, Michael and Wagner, Patrick Hermann and Wagner, Torsten and Sch{\"o}ning, Michael Josef}, title = {Light-Addressable Actuator-Sensor Platform for Monitoring and Manipulation of pH Gradients in Microfluidics: A Case Study with the Enzyme Penicillinase}, series = {Biosensors}, volume = {11}, journal = {Biosensors}, number = {6}, publisher = {MDPI}, address = {Basel}, issn = {2079-6374}, doi = {10.3390/bios11060171}, pages = {Artikel 171}, year = {2021}, abstract = {The feasibility of light-addressed detection and manipulation of pH gradients inside an electrochemical microfluidic cell was studied. Local pH changes, induced by a light-addressable electrode (LAE), were detected using a light-addressable potentiometric sensor (LAPS) with different measurement modes representing an actuator-sensor system. Biosensor functionality was examined depending on locally induced pH gradients with the help of the model enzyme penicillinase, which had been immobilized in the microfluidic channel. The surface morphology of the LAE and enzyme-functionalized LAPS was studied by scanning electron microscopy. Furthermore, the penicillin sensitivity of the LAPS inside the microfluidic channel was determined with regard to the analyte's pH influence on the enzymatic reaction rate. In a final experiment, the LAE-controlled pH inhibition of the enzyme activity was monitored by the LAPS.}, language = {en} } @inproceedings{WeldenSeverinsPoghossianetal.2022, author = {Welden, Melanie and Severins, Robin and Poghossian, Arshak and Wege, Christina and Siegert, Petra and Keusgen, Michael and Sch{\"o}ning, Michael Josef}, title = {Studying the immobilization of acetoin reductase with Tobacco mosaic virus particles on capacitive field-effect sensors}, series = {2022 IEEE International Symposium on Olfaction and Electronic Nose (ISOEN)}, booktitle = {2022 IEEE International Symposium on Olfaction and Electronic Nose (ISOEN)}, publisher = {IEEE}, isbn = {978-1-6654-5860-3 (Online)}, doi = {10.1109/ISOEN54820.2022.9789657}, pages = {4 Seiten}, year = {2022}, abstract = {A capacitive electrolyte-insulator-semiconductor (EISCAP) biosensor modified with Tobacco mosaic virus (TMV) particles for the detection of acetoin is presented. The enzyme acetoin reductase (AR) was immobilized on the surface of the EISCAP using TMV particles as nanoscaffolds. The study focused on the optimization of the TMV-assisted AR immobilization on the Ta 2 O 5 -gate EISCAP surface. The TMV-assisted acetoin EISCAPs were electrochemically characterized by means of leakage-current, capacitance-voltage, and constant-capacitance measurements. The TMV-modified transducer surface was studied via scanning electron microscopy.}, language = {en} } @article{WeldenSeverinsPoghossianetal.2022, author = {Welden, Melanie and Severins, Robin and Poghossian, Arshak and Wege, Christina and Bongaerts, Johannes and Siegert, Petra and Keusgen, Michael and Sch{\"o}ning, Michael Josef}, title = {Detection of acetoin and diacetyl by a tobacco mosaic virus-assisted field-effect biosensor}, series = {Chemosensors}, volume = {10}, journal = {Chemosensors}, number = {6}, publisher = {MDPI}, address = {Basel}, issn = {2227-9040}, doi = {10.3390/chemosensors10060218}, pages = {Artikel 218}, year = {2022}, abstract = {Acetoin and diacetyl have a major impact on the flavor of alcoholic beverages such as wine or beer. Therefore, their measurement is important during the fermentation process. Until now, gas chromatographic techniques have typically been applied; however, these require expensive laboratory equipment and trained staff, and do not allow for online monitoring. In this work, a capacitive electrolyte-insulator-semiconductor sensor modified with tobacco mosaic virus (TMV) particles as enzyme nanocarriers for the detection of acetoin and diacetyl is presented. The enzyme acetoin reductase from Alkalihalobacillus clausii DSM 8716ᵀ is immobilized via biotin-streptavidin affinity, binding to the surface of the TMV particles. The TMV-assisted biosensor is electrochemically characterized by means of leakage-current, capacitance-voltage, and constant capacitance measurements. In this paper, the novel biosensor is studied regarding its sensitivity and long-term stability in buffer solution. Moreover, the TMV-assisted capacitive field-effect sensor is applied for the detection of diacetyl for the first time. The measurement of acetoin and diacetyl with the same sensor setup is demonstrated. Finally, the successive detection of acetoin and diacetyl in buffer and in diluted beer is studied by tuning the sensitivity of the biosensor using the pH value of the measurement solution.}, language = {en} } @article{WeldenPoghossianVahidpouretal.2022, author = {Welden, Melanie and Poghossian, Arshak and Vahidpour, Farnoosh and Wendlandt, Tim and Keusgen, Michael and Wege, Christina and Sch{\"o}ning, Michael Josef}, title = {Towards multi-analyte detection with field-effect capacitors modified with tobacco mosaic virus bioparticles as enzyme nanocarriers}, series = {Biosensors}, volume = {12}, journal = {Biosensors}, number = {1}, publisher = {MDPI}, address = {Basel}, issn = {2079-6374}, doi = {10.3390/bios12010043}, pages = {Artikel 43}, year = {2022}, abstract = {Utilizing an appropriate enzyme immobilization strategy is crucial for designing enzyme-based biosensors. Plant virus-like particles represent ideal nanoscaffolds for an extremely dense and precise immobilization of enzymes, due to their regular shape, high surface-to-volume ratio and high density of surface binding sites. In the present work, tobacco mosaic virus (TMV) particles were applied for the co-immobilization of penicillinase and urease onto the gate surface of a field-effect electrolyte-insulator-semiconductor capacitor (EISCAP) with a p-Si-SiO₂-Ta₂O₅ layer structure for the sequential detection of penicillin and urea. The TMV-assisted bi-enzyme EISCAP biosensor exhibited a high urea and penicillin sensitivity of 54 and 85 mV/dec, respectively, in the concentration range of 0.1-3 mM. For comparison, the characteristics of single-enzyme EISCAP biosensors modified with TMV particles immobilized with either penicillinase or urease were also investigated. The surface morphology of the TMV-modified Ta₂O₅-gate was analyzed by scanning electron microscopy. Additionally, the bi-enzyme EISCAP was applied to mimic an XOR (Exclusive OR) enzyme logic gate.}, language = {en} } @book{Weissmantel2013, author = {Weißmantel, Ralf}, title = {Plakatzeichen : Plakate mit Schrift {\"u}ber Schrift ; 50 typografische Plakate ; Kommunikationsdesign}, publisher = {Fachhochschule Aachen, Fachbereich Design}, address = {Aachen}, isbn = {978-3-00041325-4}, pages = {51 S. : {\"u}berw. Ill.}, year = {2013}, language = {de} } @inproceedings{WeissHeslenfeldSaeweetal.2022, author = {Weiss, Christian and Heslenfeld, Jonas and Saewe, Jasmin Kathrin and Bremen, Sebastian and H{\"a}fner, Constantin Leon}, title = {Investigation on the influence of powder humidity in Laser Powder Bed Fusion (LPBF)}, series = {Procedia CIRP}, volume = {111}, booktitle = {Procedia CIRP}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2212-8271}, doi = {10.1016/j.procir.2022.08.102}, pages = {115 -- 120}, year = {2022}, abstract = {In the Laser Powder Bed Fusion (LPBF) process, parts are built out of metal powder material by exposure of a laser beam. During handling operations of the powder material, several influencing factors can affect the properties of the powder material and therefore directly influence the processability during manufacturing. Contamination by moisture due to handling operations is one of the most critical aspects of powder quality. In order to investigate the influences of powder humidity on LPBF processing, four materials (AlSi10Mg, Ti6Al4V, 316L and IN718) are chosen for this study. The powder material is artificially humidified, subsequently characterized, manufactured into cubic samples in a miniaturized process chamber and analyzed for their relative density. The results indicate that the processability and reproducibility of parts made of AlSi10Mg and Ti6Al4V are susceptible to humidity, while IN718 and 316L are barely influenced.}, language = {en} } @inproceedings{WeissAbanteribaEsch2007, author = {Weiss, Alexander and Abanteriba, Sylvester and Esch, Thomas}, title = {Investigation of Flow Separation Inside a Conical Rocket Nozzle With the Aid of an Annular Cross Flow}, series = {Proceedings of the ASME/JSME 2007 5th Joint Fluids Engineering Conference. Volume 1: Symposia, Parts A and B}, booktitle = {Proceedings of the ASME/JSME 2007 5th Joint Fluids Engineering Conference. Volume 1: Symposia, Parts A and B}, publisher = {American Society of Mechanical Engineers (ASME)}, address = {New York}, isbn = {0-7918-4288-6}, doi = {10.1115/FEDSM2007-37387}, pages = {1861 -- 1871}, year = {2007}, abstract = {Flow separation is a phenomenon that occurs in all kinds of supersonic nozzles sometimes during run-up and shut-down operations. Especially in expansion nozzles of rocket engines with large area ratio, flow separation can trigger strong side loads that can damage the structure of the nozzle. The investigation presented in this paper seeks to establish measures that may be applied to alter the point of flow separation. In order to achieve this, a supersonic nozzle was placed at the exit plane of the conical nozzle. This resulted in the generation of cross flow surrounding the core jet flow from the conical nozzle. Due to the entrainment of the gas stream from the conical nozzle the pressure in its exit plane was found to be lower than that of the ambient. A Cold gas instead of hot combustion gases was used as the working fluid. A mathematical simulation of the concept was validated by experiment. Measurements confirmed the simulation results that due to the introduction of a second nozzle the pressure in the separated region of the conical nozzle was significantly reduced. It was also established that the boundary layer separation inside the conical nozzle was delayed thus allowing an increased degree of overexpansion. The condition established by the pressure measurements was also demonstrated qualitatively using transparent nozzle configurations.}, language = {en} } @techreport{WeisSchornAnthrakidisetal.2016, author = {Weis, Fabian and Schorn, Christian and Anthrakidis, Anette and Herrmann, Ulf}, title = {Entwicklung eines kleinen Parabolrinnenkollektors mit Kunststoffkorpus zur Bereitstellung solarer Prozessw{\"a}rme : Poly-P : Abschlussbericht}, publisher = {Solar-Institut J{\"u}lich}, address = {J{\"u}lich}, pages = {56 Seiten}, year = {2016}, language = {de} } @inproceedings{WeingartSchneiderWollert2009, author = {Weingart, Daniel and Schneider, Ulf and Wollert, J{\"o}rg}, title = {Doppelt gekoppelt - Kabellose und dynamische Anbindung von CANopen an Profinet IO}, series = {Elektrische Automatisierung - Systeme und Komponenten: SPS-IPC-Drives 2009, Fachmesse \& Kongress, 24. - 26. Nov. 2009, N{\"u}rnberg ; [Tagungsband]}, booktitle = {Elektrische Automatisierung - Systeme und Komponenten: SPS-IPC-Drives 2009, Fachmesse \& Kongress, 24. - 26. Nov. 2009, N{\"u}rnberg ; [Tagungsband]}, publisher = {VDE-Verl.}, address = {Berlin [u.a.]}, isbn = {978-3-8007-3184-8}, pages = {147 -- 154}, year = {2009}, language = {de} } @inproceedings{WeilPoghossianSchoeningetal.2012, author = {Weil, M. and Poghossian, Arshak and Sch{\"o}ning, Michael Josef and Cherstvy, A.}, title = {Electrical monitoring of layer-by-layer adsorption of oppositely charged macromolecules by means of capacitive field-effect devices}, isbn = {978-3-9813484-2-2}, doi = {10.5162/IMCS2012/P2.5.2}, pages = {1575 -- 1578}, year = {2012}, language = {en} } @article{WeiheErnstRoethetal.2013, author = {Weihe, Stefan and Ernst, Ansgar and R{\"o}th, Thilo and Proksch, Johannes}, title = {Aluminium-Stahl-Verbundguss im Nutzfahrzeugbau}, series = {ATZ - Automobiltechnische Zeitschrift}, volume = {115}, journal = {ATZ - Automobiltechnische Zeitschrift}, number = {4}, publisher = {Springer Fachmedien Wiesbaden}, issn = {2192-8800 (Online)}, pages = {312 -- 316}, year = {2013}, abstract = {In modernen Fahrzeugkarosserien der Großserie kommen zunehmend Materialmischbauweisen zur Anwendung. In Zusammenarbeit der Daimler AG, der Tower Automotive Holding GmbH, der Imperia GmbH sowie der Partnerunternehmen KSM Castings GmbH und Schaufler Tooling GmbH \& Co. KG wird das Leichtbaupotenzial von Aluminiumverbundguss-Stahlblech-Hybriden am Beispiel des vorderen Dachquertr{\"a}gers des Mercedes-Benz Viano/Vito ausf{\"u}hrlich untersucht.}, language = {de} } @article{WeiheAnsgarRoethetal.2013, author = {Weihe, Stefan and Ansgar, Ernst and R{\"o}th, Thilo and Proksch, Johannes}, title = {Leichtmetall-Stahl-Verbundguss im Nutzfahrzeugbau}, series = {Lightweight Design}, volume = {6}, journal = {Lightweight Design}, number = {2}, publisher = {Springer}, address = {Berlin}, issn = {2192-8738 (Online)}, pages = {38 -- 43}, year = {2013}, abstract = {In modernen Fahrzeugkarosserien der Großserie kommen zunehmend Materialmischbauweisen zur Anwendung. In Zusammenarbeit der Daimler AG, der Tower Automotive Holding GmbH, der Imperia GmbH sowie der Partnerunternehmen KSM Castings GmbH und Schaufler Tooling GmbH \& Co. KG wird das Leichtbaupotenzial von Stahlblech-AluminiumverbundgussHybriden am Beispiel des vorderen Dachquertr{\"a}gers des Mercedes-Benz Viano/Vito ausf{\"u}hrlich untersucht.}, language = {de} } @article{WeigandCollaniSaniga1994, author = {Weigand, Christoph and Collani, E. v. and Saniga, E.M.}, title = {Economic Adjustment Design for -Control Charts. E.v.Collani, E.M. Saniga, Ch. Weigand}, series = {IIE Transactions / Institute of Industrial Engineers. 26 (1994), H. 6}, journal = {IIE Transactions / Institute of Industrial Engineers. 26 (1994), H. 6}, isbn = {0569-5554}, year = {1994}, language = {en} } @article{Weigand1994, author = {Weigand, Christoph}, title = {Optimal Production Schedule for a K Products Single Machine Problem}, series = {Economic Quality Control. 9 (1994)}, journal = {Economic Quality Control. 9 (1994)}, isbn = {0940-5151}, pages = {91 -- 101}, year = {1994}, language = {en} } @article{Weigand1991, author = {Weigand, Christoph}, title = {Optimale Maschinenjustierung}, series = {Technische Hochschule / Bibliothek: Wissenschaftliche Zeitschrift. 37 (1991)}, journal = {Technische Hochschule / Bibliothek: Wissenschaftliche Zeitschrift. 37 (1991)}, isbn = {0043-6917}, pages = {167 -- 175}, year = {1991}, language = {de} } @article{Weigand1991, author = {Weigand, Christoph}, title = {A Solution to the Scheduling Problem Taking into Account Quality}, series = {Operations research '91 : extended abstracts of the 16th Symposium on Operations Research held at the University of Trier at September 9 - 11, 1991 / [GM{\"O}OR]. Peter Gritzmann ... (eds.)}, journal = {Operations research '91 : extended abstracts of the 16th Symposium on Operations Research held at the University of Trier at September 9 - 11, 1991 / [GM{\"O}OR]. Peter Gritzmann ... (eds.)}, publisher = {Physica-Verl.}, address = {Heidelberg}, isbn = {3790806080}, pages = {373 -- 375}, year = {1991}, language = {en} } @article{Weigand1990, author = {Weigand, Christoph}, title = {Optimal Adjustment Policies}, series = {Proceedings of the First Ume{\aa}-W{\"u}rzburg Conference in Statistics : Kronlund Conference Center and University of Ume{\aa}, September 10 - 14, 1990 / ed. by Kurt Br{\"a}nn{\"a}s}, journal = {Proceedings of the First Ume{\aa}-W{\"u}rzburg Conference in Statistics : Kronlund Conference Center and University of Ume{\aa}, September 10 - 14, 1990 / ed. by Kurt Br{\"a}nn{\"a}s}, publisher = {Univ. of Ume{\aa}}, address = {Ume{\aa}}, isbn = {91-7174-564-5}, pages = {147 -- 158}, year = {1990}, language = {en} } @book{Weigand2006, author = {Weigand, Christoph}, title = {Statistik mit und ohne Zufall : eine anwendungsorientierte Einf{\"u}hrung ; mit 10 Tabellen / Christoph Weigand}, publisher = {Physica-Verl.}, address = {Heidelberg}, isbn = {3-7908-1693-0}, pages = {XIII, 421 S. : graph. Darst.}, year = {2006}, language = {de} } @article{Weigand2003, author = {Weigand, Christoph}, title = {Technically Optimal Inspection Policy with Arithmetical Adaption}, series = {IMA Journal of Management Mathematics. 14 (2003), H. 4}, journal = {IMA Journal of Management Mathematics. 14 (2003), H. 4}, isbn = {1471-678X}, pages = {357 -- 371}, year = {2003}, language = {en} } @article{Weigand2003, author = {Weigand, Christoph}, title = {Economically Optimal Inspection Policy with Geometrical Adaption}, series = {Journal of Applied Statistics. 30 (2003), H. 5}, journal = {Journal of Applied Statistics. 30 (2003), H. 5}, isbn = {0266-4763}, pages = {555 -- 569}, year = {2003}, language = {en} }