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Der Energiebedarf von Pumpensystem entspricht etwa 8% bis 9% des weltweiten elektrischen Energieverbrauchs. Folglich hat die Energieeffizienz von Pumpensystemen einen signifikanten Einfluss auf den weltweiten Energiebedarf. Der Fokus dieser Arbeit liegt auf der Betrachtung von Pumpenaggregaten, welche in Wärme- und Kältesystemen eingesetzt werden. In diesem Anwendungsbereich kann der Energieverbrauch durch den Einsatz energieeffizienter Regelungskonzepte im Vergleich zum konventionellen ...
The human cell is constantly confronted with reactive oxygen species (ROS), which are oxygen-containing chemical intermediates readily reacting with different biomolecules. ROS can originate from exogenous sources, but are also produced within cells, e.g. as part of their metabolism. Depending on the concentration, ROS can either act as important signaling molecules or induce oxidative stress, thereby harming cellular components. Thus, cells utilize a multitude of antioxidant mechanisms to ma...
Apart from the widely known duplex structure DNA can fold into various secondary structures such as hairpin loops, triplexes and G-quadruplexes. The latter self-assemble from guanine rich strands by Hoogsteen base pairing to form stacked guanine tetrads. Since their discovery, G-quadruplexes became increasingly interesting in the field of chemical biology due to their property to control the elongation of telomeres and the expression of oncogenes. Furthermore, first examples of a DNAzyme acti...
Synthetic organic dyes find broad use in industry (e.g. as colorizing agents and laser materials), medicine (e.g. as diagnostic tools and drugs) and research (e.g. in fluorescence microscopy, FRET setups and as photosensitizers). All the applications originate from the typical interaction that these chromophores have with visible light. However, while a number of these dyes is produced on a multi ton scale since decades, their implementation into complex chemical systems and nano structures s...
The aim of this work is the development of a method to operate elementary spin excitations (magnons) in a ferromagnetic metal by means of elementary vibrational excitations of the lattice (phonons). The utilized magnon-phonon coupling was confirmed more than 50 years ago, but only recently the experimental approaches of ultrafast acoustics have made available the excitation and time-resolved detection of coherent phonons in the sub-THz frequency range. The most intriguing regime of the magnon...
In the process industries the optimal allocation of shared resources among physically coupled subsystems is key to an efficient operation of the overall system, e. g., an integrated production site. If the subsystems have a certain level of autonomy or it is desired to grant confidentiality to the constituent subsystems, price-based coordination can be employed, where an independent system operator (ISO) iteratively adjusts transfer prices for the shared resources until the demand and the sup...
Many industrial processes are coupled via multiple networks of energy and materials to achieve a resource and energy efficient production. In many cases however, setting up an integrated optimization problem for all units or plants that are directly connected to the networks is not possible, especially when not all information can be shared. In such cases, dual decomposition or price-based coordination can be used, where optimal transfer prices are iteratively determined at which the networks...
A strategy to implement four members of the classic coal-tar dye family, Michler´s ketone, methylene blue, rhodamine B and crystal violet, into [Pd2L4] self-assemblies is introduced. Chromophores were incorporated into bis-monodentate ligands using piperazine linkers that allow to retain the auxochromic dialkyl amine functionalities required for intense colors deep in the visible spectrum. Upon palladium coordination, ligands with pyridine donors form lantern-shaped dinuclear cages while quin...
The combination of shape-complementary bis-monodentate ligands LA and LB with PdII cations yields heteroleptic cages cis-[Pd2LA2LB2] by self-sorting. Herein, we report how such assemblies can be diversified by introduction of covalent backbone bridges between two LA units. Together with solvent and guest effects, the flexibility of these linkers can modulate nuclearity, topology, and number of cavities in a family of four structurally diverse assemblies. Ligand LA1, with flexible linker, reac...
We study an imbibition problem for porous media. When a wetted layer is above a dry medium, gravity leads to the propagation of the water downwards into the medium. In experiments, the occurence of fingers was observed, a phenomenon that can be described with models that include hysteresis. In the present paper we describe a single finger in a moving frame and set up a free boundary problem to describe the shape and the motion of one finger that propagates with a constant speed. We show the exis...
Das Konzept der Umweltgerechtigkeit (UG) bezieht sich inhaltlich auf die Beziehung zwischen der sozialen Lage einer Person, ihrer lokalen Umwelt und Gesundheit. Dabei wird die sozialräumliche Verteilung von Umweltbelastungen und -ressourcen in den Blick genommen. Somit vereint das Umweltgerechtigkeitskonzept ökologische und soziale Anforderungen an den Siedlungsraum. Anknüpfungspunkte für die Stadtplanung und -entwicklung finden sich in vielen informellen Zielsetzungen und formalen Regelwerke...
The study Health and Support in Times of Corona was conducted during May to June 2020 to examine the recent changes in health, support systems, and wellbeing of middle-aged and older adults during the COVID-19 pandemic in Germany. Given many of the mitigation measures revolved around physical distancing to reduce the spread of the virus, the specific objectives were to assess: 1) Health Care: The extent to which individuals’ access to and utilization of health and formal care services have b...
The principal axes of this thesis project are the synthesis of tripodal tris(organostannylmethyl)silanes of the type MeSi(CH2SnR(3–n)Xn)3 (n = 0– 3; X = I, F, Cl, Br; R = Ph, CH2SiMe3) , as building blocks for the synthesis of novel organostannate complexes and umprecedented organotin chlacogeno-clusters among which novel triangular belt-shaped diorganotin oxo clusters [MeSi(CH2SnRO)3]n, R = Ph, CH2SiMe3 with gigantic nuclearity; oktokaideka (n = 18) and trikonta (n = 30). Furthermore, format...
Many materials in the field of continuum mechanics can be considered, at least in parts, as rate-independent. Such systems are generally driven by external forces and thereby independent of their speed (rate) but still dependent on their direction. In this dissertation, we consider rate-independent systems which can be described by means of a, in general, nonconvex energy and a positively homogeneous dissipation. Both properties in combination allow the formation of abrupt changes in sta...
In diesem Dokument werden zwei Analysen auf dem Gebiet der Teilchenphysik vorgestellt. Erstens, Studien über die Performanz der Rekonstruktion von Myonen unter Verwendung von Kalorimeterinformationen während der HL-LHC Phase des ATLAS Detektors. Zweitens, die Suche nach der simultanen Produktion von vier Top-Quarks, wie vom Standard Modell (SM) prognostiziert, unter Verwendung des vollständigen Run-II-Datensatzes, der von ATLAS aufgenommen wurde. Dieser Datensatz entspricht einer integrierten...
Im Gegensatz zu früheren Dekaden der Stadtentwicklung, in der Städte sich durch weitgehend konstante Anstiege der Bevölkerungszahl und Wirtschaftskraft auszeichneten, unterliegen viele Kommunen heute Stagnations- oder sogar Schrumpfungsprozessen. Wachstum wie auch Schrumpfung stellen die Stadtentwicklung vor erhebliche Herausforderungen. Für viele Kommunen bestehen diese Aufgaben auch in der Bewältigung der Folgewirkungen des Truppenabbaus. Im Ausgangspunkt der Arbeit besteht die Annahme, das...
Lipid membranes are crucial components of living cells. They constitute the outer shell and separate intracellular compartments and organelles. To regulate the mass transfer between the separated regions, they undergo remodeling processes like fusion and budding. In the framework of this thesis, it was examined how viral fusion peptides, cellular solutes and cholesterol modulate the behavior of lipid structures. In a small angle X-ray scattering study on monoolein mesophases, it was explored ...
Angesichts der COVID-19-Pandemie, die plötzliche Veränderungen in vielen Lebensbereichen nach sich zieht, wurde im Forschungsfeld „Alternde Gesellschaften“ der Technischen Universität Dortmund eine Pilotstudie durchgeführt. Ziel der Studie „Gesundheit und Unterstützung in Zeiten von Corona“ war es, Erkenntnisse darüber zu gewinnen, wie sich die COVID-19-Pandemie auf das Gesundheitsverhalten, Lebenszufriedenheit und Wohlbefinden sowie auf geleistete und erhaltene Unterstützung von Personen im ...
Throughout the different scales at which living organisms operate, it is the collective behaviour between the entities that compose them that determines their identity and function. Biomolecules, cells and whole organisms interact to process information and generate organization at the subcellular, tissue and ecosystem scales. In the first part of this thesis, we investigated fundamental principles of cellular morphogenesis in response to external cues in a Synthetic Morphogenic Membrane...
In jedem Lebewesen findet eine Vielzahl verschiedener biochemischer Reaktionen statt, die durch Enzyme vermittelt werden. Angesichts verschiedener Vorteile gegenüber chemischen Katalysatoren besteht ein großes Interesse an der Verwendung solcher Biokatalysatoren in industriellen Prozessen. Um die Produktausbeute einer Reaktion bzw. katalytischen Eigenschaften eines Enzyms noch weiter zu optimieren, werden heutzutage mittels zielgerichtetem Proteindesign, Immobilisierungstechniken sowie durch ...