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Item Open Access Detuning dependent Rabi oscillations of a single molecule(2019) Rezai, Mohammad; Wrachtrup, Jörg; Gerhardt, IljaA single organic dye molecule at cryogenic conditions is resonantly excited in a confocal microscope. Under strong laser illumination it undergoes Rabi oscillations. Mathematically, this was well described and had been experimentally implemented. These oscillations can be measured as side-bands on their resonance fluorescence, e.g. in the Mollow-Triplet. An alternative method is to research this effect by an analysis of the single molecule anti-bunched photon statistics. This has been performed in this work. Here we research on the detuning dependence of this signal-it is experimentally demanding since the utilized laser might drift or single emitters are not necessarily spectrally stable enough, such that the spectrum can be measured indefinitely. We therefore apply a measurement technique in which the photon correlation signal is acquired in detuning dependent steps. This is performed by continuous laser sweeps over the single molecule excitation spectrum. A single recording of the anti-bunched photons takes 20-50 ms. After approx. 1 h of repetitive laser detunings a full anti-bunching curve is reconstructed for each spectral position. An alternative technique with 100 ns laser pulses allows us to acquire a set of comparable data. Our study is derived from a single dibenzanthanthrene molecule with a natural linewidth of 2π×16 MHz. It emits under resonant excitation more than 380.000 photons per second. Under spectral detuning, Rabi-oscillations are observed up to ΩRabi = 2π×160 MHz.Item Open Access Moment dynamics of Zirconia particle formation for optimizing particle size distribution(2019) Halter, Wolfgang; Eisele, Rahel; Rothenstein, Dirk; Bill, Joachim; Allgöwer, FrankItem Open Access Effects of chemical modifications on the rheological and the expansion behavior of polylactide (PLA) in foam extrusion(2019) Standau, Tobias; Castellón, Svenja Murillo; Delavoie, Agathe; Bonten, Christian; Altstädt, VolkerIt is well known that polylactide (PLA) is difficult to foam due to its low melt strength. Thus, many ways were described in the literature to enhance the foamability. However, the melt strength was actually determined only in a limited number of publications. In this study, the addition of chemical modifiers was used to change the rheological behavior of PLA and thereby improve its foamability in foam extrusion process. For the first time the use of dicumyl peroxide modified PLA in foam extrusion is described. Both modifications lead to a distinct increase in melt strength. Here, the highest increase was shown for the PLA modified with dicumyl peroxide. Furthermore, strain hardening was observed for PLA modified with the peroxide. Low density foams were achieved for neat and modified PLA in foam extrusion. Neat PLA showed a density of 45 kg/m 3 , while the peroxide modified PLA showed the highest expansion with a density reduction down to 32 kg/m 3 . Both modifications result in a more uniform cell structure and an improved compression strength. Here, the foamed, peroxide modified PLA showed outstanding performance compared to neat PLA foam with twice the compression strength (151 Pa) even at a 30% lower density.Item Open Access Mechatronic control system for a compliant and precise pneumatic rotary drive unit(2019) Stoll, Johannes T.; Schanz, Kevin; Pott, AndreasItem Open Access Inversely 3D-printed β-TCP scaffolds for bone replacement(2019) Seidenstücker, Michael; Lange, Svenja; Esslinger, Steffen; Latorre, Sergio H.; Krastev, Rumen; Gadow, Rainer; Mayr, Hermann O.; Bernstein, AnkeItem Open Access Fully-resolved simulations of coal particle combustion using a detailed multi-step approach for heterogeneous kinetics(2019) Tufano, Giovanni Luigi; Stein, Oliver T.; Kronenburg, Andreas; Gentile, Giancarlo; Stagni, Alessandro; Frassoldati, Alessio; Faravelli, Tiziano; Kempf, Andreas M.; Vascellari, Michele; Hasse, ChristianItem Open Access A novel approach for reliability investigation of LEDs on molded interconnect devices based on FE-analysis coupled to injection molding simulation(2019) Soltani, Mahdi; Kulkarni, Romit; Scheinost, Tobias; Groezinger, Tobias; Zimmermann, AndréItem Open Access Scaling the productivity of laser structuring processes using picosecond laser pulses at average powers of up to 420W to produce superhydrophobic surfaces on stainless steel AISI 316L(2019) Faas, Sebastian; Bielke, Uwe; Weber, Rudolf; Graf, ThomasItem Open Access Review on fabrication technologies for optical mold inserts(2019) Röder, Marcel; Guenther, Thomas; Zimmermann, AndréPolymer optics have gained increasing importance in recent years. With advancing requirements for the optical components, the fabrication process remains a challenge. In particular, the fabrication of the mold inserts for the replication process is crucial for obtaining high-quality optical components. This review focuses on fabrication technologies for optical mold inserts. Thereby, two main types of technologies can be distinguished: fabrication methods to create mold inserts with optical surface quality and methods to create optical microstructures. Since optical mold inserts usually require outstanding form accuracies and surface qualities, a focus is placed on these factors. This review aims to give an overview of available methods as well as support the selection process when a fabrication technology is needed for a defined application. Furthermore, references are given to detailed descriptions of each technology if a deeper understanding of the processes is required.Item Open Access Integration of LCA in the planning phases of adaptive buildings(2019) Schlegl, Friederike; Honold, Clemens; Leistner, Sophia; Albrecht, Stefan; Roth, Daniel; Haase, Walter; Leistner, Philip; Binz, Hansgeorg; Sobek, WernerThe high consumption of resources in the building industry requires a significant reduction of material in buildings and consequently a reduction of emissions over all phases of the life cycle. This is the aim of the Collaborative Research Centre 1244 Adaptive Skins and Structures for the Built Environment of Tomorrow, funded by the German Research Foundation (DFG), which addresses research on the development and integration of adaptive systems in building structures and skins. New approaches in building planning are required for the implementation of adaptive buildings. Therefore, a multidisciplinary team from various fields such as architecture, civil and mechanical engineering, and system dynamics is necessary. The environmental impacts of the whole life cycle have to be considered for an integral planning process for adaptive buildings right from the beginning. For the integration of the Life Cycle Assessment (LCA), four temporal and content-related interfaces were identified in the planning process. Inputs and outputs of the LCA were defined for the relevant planning stages in order to enable the greatest possible benefit for the planners and to minimize the environmental impacts as far as possible. The result of the research work is a methodology that can be used in the future to reduce life cycle-related environmental impacts in the planning process of adaptive buildings (ReAdapt).