TY - CONF AU - Stallmeister, Tim AU - Chalicheemalapalli Jayasankar, Deviprasad AU - Wang, Z. AU - Tröster, Thomas ID - 16033 TI - Selbstabdichtendes Werkzeugkonzept für RTM-Prozesse ER - TY - JOUR AU - Herberg, Artjom AU - Yu, Xiaoqian AU - Kuckling, Dirk ID - 30932 IS - 4 JF - Polymers KW - controlled radical polymerization KW - atom transfer radical polymerization KW - end group determination KW - N-isopropylacrylamide KW - block copolymerization KW - smart polymers KW - temperature sensitive polymers KW - lower critical solution temperature KW - ESI-TOF mass spectrometry KW - ion mobility separation KW - size exclusion chromatography TI - End Group Stability of Atom Transfer Radical Polymerization (ATRP)-Synthesized Poly(N-isopropylacrylamide): Perspectives for Diblock Copolymer Synthesis VL - 11 ER - TY - JOUR AU - Li, Jie AU - Ji, Chendong AU - Yu, Xiaoqian AU - Yin, Meizhen AU - Kuckling, Dirk ID - 30929 IS - 14 JF - Macromolecular Rapid Communications KW - Materials Chemistry KW - Polymers and Plastics KW - Organic Chemistry SN - 1022-1336 TI - Dually Cross‐Linked Supramolecular Hydrogel as Surface Plasmon Resonance Sensor for Small Molecule Detection VL - 40 ER - TY - JOUR AU - Reis, Berthold AU - Vehlow, David AU - Rust, Tarik AU - Kuckling, Dirk AU - Müller, Martin ID - 30927 IS - 23 JF - International Journal of Molecular Science KW - catechol chemistry KW - poly(caffeic acid) KW - polyelectrolyte complex coatings KW - thermoresponsive coatings KW - controlled release KW - bortezomib KW - multiple myeloma TI - Thermoresponsive Catechol Based-Polyelectrolyte Complex Coatings for Controlled Release of Bortezomib VL - 20 ER - TY - JOUR AU - Yu, Xiaoqian AU - Herberg, Artjom AU - Kuckling, Dirk ID - 30928 JF - European Polymer Journal KW - Organic Chemistry KW - Polymers and Plastics KW - General Physics and Astronomy KW - Materials Chemistry SN - 0014-3057 TI - Azlactone-functionalized smart block copolymers for organocatalyst immobilization VL - 120 ER - TY - JOUR AU - Mahlert, Laura AU - Anderski, Juliane AU - Schoppa, Timo AU - Mulac, Dennis AU - Sun, Jingjiang AU - Kuckling, Dirk AU - Langer, Klaus ID - 30934 JF - International Journal of Pharmaceutics KW - Light-responsive polymersPhotodynamic therapyControlled drug deliveryHT-29-MTX cellsIntestinal cancer SN - 0378-5173 TI - In vitro evaluation of innovative light-responsive nanoparticles for controlled drug release in intestinal PDT VL - 565 ER - TY - JOUR AU - Sun, Jingjiang AU - Jung, Dimitri AU - Schoppa, Timo AU - Anderski, Juliane AU - Picker, Marie-Theres AU - Ren, Yi AU - Mulac, Dennis AU - Stein, Nora AU - Langer, Klaus AU - Kuckling, Dirk ID - 30936 IS - 7 JF - ACS Applied Bio Materials KW - light-responsive polymers KW - biodegradable polymers KW - polycondensation SN - 2576-6422 TI - Light-Responsive Serinol-Based Polycarbonate and Polyester as Degradable Scaffolds VL - 2 ER - TY - JOUR AU - Sun, Jingjiang AU - Anderski, Juliane AU - Picker, Marie-Theres AU - Langer, Klaus AU - Kuckling, Dirk ID - 30933 IS - 5 JF - Macromolecular Chemistry and Physics KW - Materials Chemistry KW - Organic Chemistry KW - Polymers and Plastics KW - Physical and Theoretical Chemistry KW - Condensed Matter Physics SN - 1022-1352 TI - Preparation of Light-Responsive Aliphatic Polycarbonate via Versatile Polycondensation for Controlled Degradation VL - 220 ER - TY - JOUR AB - This article offers new insight into students’ responses to Womens’ and Gender Studies (WGS) classes by overcoming the self-selection bias hitherto inherent in the field. Exploring the experiences of 1406 students (770 women, 636 men) of a university with a WGS requirement across all study programmes, we examine the prevailing discourses on WGS, participants’ (dis)agreement as well as personal and professional benefits gained through WGS. Additionally, we evaluate the perceived value of WGS for themselves, in society, and of WGS opportunities in higher education. Findings reveal a gender bias regarding discourses, experience, benefit, and value, with 70.1% women and 32.4% men supporting the idea of WGS as a mandatory subject. Women’s support indicates a need for tools to negotiate gender issues, while men’s resistance serves to defend male privileges. We conclude that a requirement of WGS classes amplifies the potential for both – resistance and change. AU - Horwath, Ilona AU - Diabl, Christian ID - 24462 JF - Gender and Education KW - Education policy KW - equality KW - higher education KW - critical pedagogies KW - gender mainstreaming KW - curriculum SN - 0954-0253 TI - Liberating or indoctrinating? Surveying students’ perceptions of a Womens’ and Gender Studies requirement ER - TY - CONF AU - Terhechte, Johannes AU - Berscheid, Anna Lena AU - Horwath, Ilona ID - 24464 TI - DEVELOPMENT OF A CYBER-PHYSICAL SIMULATION ASSISTANCE SYSTEM FOR PARTIALLY AUTOMATED OPTIMIZATION OF THE EXTRUSION PROCESS ER - TY - JOUR AU - Berscheid, Anna Lena AU - Horwath, Ilona AU - Riegraf, Birgitt ID - 24460 JF - Feministische Studien SN - 2365-9920 TI - Einleitung: Cyborgs revisited: Zur Verbindung von Geschlecht, Technologien und Maschinen ER - TY - CONF AU - Vorderbrüggen, Julian AU - Gröger, Benjamin AU - Kupfer, Robert AU - Hoog, Arne AU - Gude, Maik AU - Meschut, Gerson ID - 19893 T2 - PROCEEDINGS OF THE 22ND INTERNATIONAL ESAFORM CONFERENCE ON MATERIAL FORMING: ESAFORM 2019 TI - Phenomena of forming and failure in joining hybrid structures – Experimental and numerical studies of clinching thermoplastic composites and metal ER - TY - JOUR AU - Vorderbrüggen, Julian AU - Meschut, Gerson ID - 19894 JF - Composite Structures SN - 0263-8223 TI - Investigations on a material-specific joining technology for CFRP hybrid joints along the automotive process chain ER - TY - JOUR AB - Plastic freeforming (PF) is an additive-manufacturing process for producing three-dimensional plastic parts based on 3D CAD data by applying plastic droplets in layers. This process is used to produce customer-specific and complex geometries (prototypes and small series) on organic sheets. A comparable serial process is the injection of a second component onto organic sheets by injection molding. A sufficient bond between the PF structure and the organic sheets is of particular importance for each application. If this is not guaranteed, the composite system cannot withstand the mechanical load and fails. The force exerted on the system can no longer be transmitted between the PF structure and the organic sheet. The organic sheet is made of glass fiber-reinforced polypropylene (PP). The connection between the organic sheet and the PF structure is achieved by welding the molten polymer droplets and the surface of the organic sheet. The PF structures are made of PP to ensure sufficient compatibility with regard to the weldability of the components. The processing of PP in the PF process is a challenge because PP is a semicrystalline material. The shrinkage of semi-crystalline materials is significantly higher compared to amorphous materials. Due to the layered structure of the components, the shrinkage of the individual layers results in undesired warpage. The adhesive strength between the organic sheet and the PF structure is investigated by determining the bending strength in the 3-point bending test. The investigations include an optimization of the process parameters to maximize the adhesive strength. The experimental investigations show that an increase of the nozzle and build chamber temperature leads to a higher adhesive strength. In further investigations, the temperature of the nozzle shows no significant influence on the surface temperature despite the expected heat radiation. The surface temperature is almost only dependent on the temperature of the build chamber. AU - Moritzer, Elmar AU - Hirsch, André AU - Heim, H.P. AU - Cherif, C. AU - Truemper, W. ID - 22047 JF - Welding in the World TI - Plastic droplet welding: bond strength between plastic freeforming structures and continuous fiber-reinforced thermoplastic composites VL - 63 ER - TY - CONF AB - The mechanical properties of thin-walled plastic components are limited. One approach to improve the strength or stiffness of these components is to reinforce the thin-walled areas with an individually adapted Fused Deposition Modeling structure. Fused Deposition Modeling (FDM) is one of the most commonly used additive manufacturing processes. This process is characterized by the deposition of a fused, thermoplastic filament. Depending on the form of the reinforcement structure, the resulting hybrid structure should show higher strength or stiffness. The objective of the project is to determine constructive design and process guidelines for FDM structures. The FDM structure is to be used as a partial reinforcement for lightweight components and be adapted to the respective load conditions. Because of the lightweight application, the FDM structure should also have the lowest possible weight. The optimization of the FDM parts for different load cases is realized by adapting the design parameters. These parameters influence the layer generation and therefore also the inner structure of the FDM parts. In preliminary studies, the manufacturing restrictions of the FDM process are defined. The specimens are manufactured based on the Design of Experiments. To determine the static strength properties, different tests (tensile, compression, flexural, torsion and impact) are carried out. The investigations show that the filling strategy affects the mechanical properties. As a result of the investigations, design and process guidelines for the FDM structures are established according to the load conditions. AU - Moritzer, Elmar AU - Hirsch, André AU - Bürenhaus, Franziska Isabelle ID - 22028 IS - 1 T2 - AIP Conference Proceedings TI - Development and Modeling of Design and Process Guidelines for FDM Structures for the Partial Reinforcement of Hybrid Structures VL - 2065 ER - TY - CONF AB - Additive manufacturing processes, like the Fused Deposition Modeling (FDM) process, do not need product-specific tools and create parts directly from the CAD data. In the FDM process, the semi-finished product, a wire of a thermoplastic polymer, is melted and forced through a nozzle. The continuous positioning of this nozzle allows the polymer to weld together strand by strand and layer by layer to produce a component. Because no mold is used in the FDM process, no holding pressure can be generated as in injection molding processes, in which the holding pressure is used to minimize the shrinkage and warpage of the part. In the FDM process, the part is generated in an ambient pressure environment. Each strand cools down and shrinks separately. This causes residual stresses in the part that can lead to major warpage and a complete stoppage of the process. This is the main reason why the material selection in the FDM process is restricted in comparison to conventional polymer processing technologies. In this paper, the warpage of different polymers is quantified as a criterion for evaluating the processability of polymers in the FDM process. Due to the process principle, the part properties in the FDM process are mainly influenced by the machine quality and the data processing, so that it is difficult to test a material for FDM independently of the machine and the data processing. Considering these influences, a custom-built specimen is created to test and quantify the warpage of different types of blended and reinforced polyamide 6. Considering the experimentally investigated warpage, the materials can be evaluated and the warpage can be related to the shrinkage investigated in pvT measurements. This procedure allows the machine- and process-independent rating of the processability in terms of warpage for different materials. Alongside other criteria, this is a necessary step to develop new materials with good processability in the FDM process. AU - Schöppner, Volker AU - Schumacher, C. AU - Fels, C. ID - 22027 T2 - AIP Conference Proceedings TI - A Method to Evaluate the Process-Specific Warpage for Different Polymers in the FDM Process ER - TY - BOOK AB - Das Fused Deposition Modeling (FDM) ist ein etabliertes additives Fertigungsverfahren zur Her-stellung von thermoplastischen Kunststoffbauteilen. In dem vorliegenden Beitrag sind FDM-Verstärkungsstrukturen aus dem Material Ultem 9085 dynamischen Langzeituntersuchungen un-terzogen worden. Dabei wurde die innere Struktur der Probekörper über eine Parametervariation verändert, sodass anschließend die signifikanten Einflussfaktoren auf die Langzeitfestigkeit un-ter dynamischer Belastung identifiziert und analysiert werden konnten. Mit dieser Vorgehens-weise sollte gleichzeitig eine Optimierung der FDM-Verstärkungsstrukturen hinsichtlich der dy-namischen Langzeiteigenschaften bei Biege- und Druckbelastungen vorgenommen werden. Des Weiteren sind anhand der Probekörper die auftretenden Bruch- und Rissausbreitungsmechanis-men analysiert worden. Anhand der ermittelten Wöhlerkurven kann die Lebensdauer unter dy-namischer Belastung abgeschätzt werden. Außerdem zeigen die Untersuchungen, dass Fehlstel-len durch eine hohe Strangbreite und Überfüllungen im Bauteil für Schwachstellen in den FDM-Verstärkungsstrukturen sorgen, an denen Risse bei Druckbelastung entstanden sind und sich dadurch schneller ausbreiten konnten. AU - Moritzer, Elmar AU - Hirsch, André AU - Paulus, S. ID - 22026 SN - 978-3-658-27411-5 TI - Rissausbreitungsmechanismen in FDM-Verstärkungsstrukturen unter dynamischer Beanspruchung ER - TY - THES AU - Bolte, Sven ID - 30854 TI - Modellierung und Optimierung leistungselektronischer Konverter mit Halbleitern großer Bandlücke unter Verwendung kalorimetrischer Messverfahren ER - TY - THES AB - Hochgeschwindigkeitsantriebe kommen unter anderem in Vakuumpumpen, Turboradialverdichtern und Zentrifugen zum Einsatz und zeichnen sich typischerweise durch einen Betrieb mit konstanter Drehzahl über längere Zeiträume aus. Das in dieser Arbeit betrachtete Antriebssystem setzt sich aus einer permanentmagneterregten Synchronmaschine mit magnetgelagertem Rotor, einem LC-Filter, einem Wechselrichter in 2- oder 3-Stufen-Topologie, diverser Sensorik sowie einem Antriebsregler zusammen. In der vorliegenden Arbeit wurden Pulsmusterformen auf viertel- und halbschwingungssymmetrischer Basis ausgewählt und nach relevanten Kriterien wie die Eliminierung niederfrequenter Harmonischer oder die Minimierung des Oberschwingungsgehalts offline-optimiert. Hierzu wurde eine modifizierte Variante der Partikel-Schwarm-Optimierung verwendet. Ziel war die Substitution der trägerbasierten Dreiecksmodulation durch eine geeignete Modulatorstruktur zur Generierung und Ausgabe offline-optimierter Pulsmuster an den Wechselrichter. Im Verlauf der Arbeit wurde zudem herausgestellt, dass die herkömmliche feldorientierte Reglerstruktur nicht mit den optimierten Pulsmustern kombiniert werden kann, was auf die fehlende Pulssymmetrie und die abweichenden Kurzzeitmittelwerte der Schaltsignale von der Stellspannung im aktuellen Reglertakt zurückzuführen ist. Daher wurde eine modellbasierte Reglerstruktur, die zum Teil steuernden Charakter aufweist, entworfen und implementiert. Durchgeführte Messungen an einem Laststand mit einer Bemessungsleistung von 150 kW ergaben im maximal zulässigen Arbeitspunkt gegenüber der dreiecksmodulierten Pulsweitenmodulation eine Steigerung des Gesamtwirkungsgrads von bis zu 0,6% bei Verwendung eines 2-Punkt-Wechselrichters mit ausgangsseitigem LC-Filter. AU - Peter, Klaus ID - 29903 SN - 978-3-8440-7097-2 TI - Untersuchung des Verlustverhaltens eines geregelten und mit optimierten Pulsmustern gespeisten Hochgeschwindigkeits-Antriebssystems VL - 9 ER - TY - THES AU - Pape, Thorsten ID - 30855 SN - 978-3-8440-6952-5 TI - Ein Beitrag zur Regelung von Permanentmagnet-Synchronmotoren in Statorflusskoordinaten ohne Rotorlagesensor ER -