In the present work, we discuss two subjects related to the nonequilibrium dynamics of polymers or biological filaments adsorbed to two-dimensional substrates. <br><br> The first part is dedicated to thermally activated dynamics of polymers on structured substrates in the presence or absence of a driving force. The structured substrate is represented by double-well or periodic potentials. We consider both homogeneous and point driving forces. Point-like driving forces can be realized in single molecule manipulation by atomic force microscopy tips. Uniform driving forces can be generated by hydrodynamic flow or by electric fields for charged polymers. <br><br> In the second part, we consider collective filament motion in motility assays for motor proteins, where filaments glide over a motor-coated substrate. The model for the simulation of the filament dynamics contains interactive deformable filaments that move under the influence of forces from molecular motors and thermal noise. Motor tails are attached to the substrate and modeled as flexible polymers (entropic springs), motor heads perform a directed walk with a given force-velocity relation. We study the collective filament dynamics and pattern formation as a function of the motor and filament density, the force-velocity characteristics, the detachment rate of motor proteins and the filament interaction. In particular, the formation and statistics of filament patterns such as nematic ordering due to motor activity or clusters due to blocking effects are investigated. Our results are experimentally accessible and possible experimental realizations are discussed. / In der vorliegenden Arbeit behandeln wir zwei Probleme aus dem Gebiet der Nichtgleichgewichtsdynamik von Polymeren oder biologischen Filamenten, die an zweidimensionale Substrate adsorbieren. <br><br> Der erste Teil befasst sich mit der thermisch aktivierten Dynamik von Polymeren auf strukturierten Substraten in An- oder Abwesenheit einer treibenden Kraft. Das strukturierte Substrat wird durch Doppelmulden- oder periodische Potentiale dargestellt. Wir betrachten sowohl homogene treibende Kräfte als auch Punktkräfte. Punktkräfte können bei der Manipulation einzelner Moleküle mit die Spitze eines Rasterkraftmikroskops realisiert werden. Homogene Kräfte können durch einen hydrodynamischen Fluss oder ein elektrisches Feld im Falle geladener Polymere erzeugt werden. <br><br> Im zweiten Teil betrachten wir die kollektive Bewegung von Filamenten in Motility-Assays, in denen Filamente über ein mit molekularen Motoren überzogenes Substrat gleiten. Das Modell zur Simulation der Filamentdynamik beinhaltet wechselwirkende, deformierbare Filamente, die sich unter dem Einfluss von Kräften, die durch molekulare Motoren erzeugt werden, sowie thermischem Rauschen bewegen. Die Schaftdomänen der Motoren sind am Substrat angeheftet und werden als flexible Polymere (entropische Federn) modelliert. Die Kopfregionen der Motoren vollführen eine gerichtete Schrittbewegung mit einer gegebenen Kraft-Geschwindigkeitsbeziehung. Wir untersuchen die kollektive Filamentdynamik und die Ausbildung von Mustern als Funktion der Motor- und der Filamentdichte, der Kraft-Geschwindigkeitscharakteristik, der Ablöserate der Motorproteine und der Filamentwechselwirkung. Insbesondere wird die Bildung und die Statistik der Filamentmuster, wie etwa die nematische Anordnung aufgrund der Motoraktivität oder die Clusterbildung aufgrund von Blockadeeffekten, untersucht. Unsere Ergebnisse sind experimentell zugänglich und mögliche experimentelle Realisierungen werden diskutiert.

Maleimide based highly luminescent material Cbz-MI with donor acceptor donor (D-A-D) backbone has been synthesized and characterized. An organic light emitting diode fabricated using this material as emitting layer exhibited EQE of 2.5% in the yellow region of visible spectrum. Due to the small energy gap of materials emitting in this region of spectrum, EQE of OLED is usually limited by various non-radiative decays and high EQE of OLED using this material proves that most of the nonradiative decay pathways have been avoided by the careful design of molecule and device structure. Although Cbz-MI did not show TADF properties, but if tailored with right electron donor along with maleimide as an acceptor, such derivatives may exhibit TADF properties

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The diploma thesis focuses on assesment of water quality in heating systems. The experiment includes description of used methods and meters as well as analysis of collected samples. The theoretical part describes selected water properties, quality meters and sources of heat according to the material of their heat exchanger. This thesis processes design of heating system and hot water preparation for complex of administration buildings. The project includes calculations of heat losses, system proposal and two versions of possible heat source. The first version offers solution with condensing boiler with heat exchanger from stainless steel, while the second version uses condensing boiler with heat exchanger from aluminium and silicon. Both versions have their own solution of safety equipment and water treatment.

As the third generation of luminescent materials, thermally activated delayed fluorescence (TADF)-type compounds have great potential as emitter molecules in OLEDs allowing for electro-fluorescence with 100 % internal quantum efficiency. For organic electronics, the general wide range of applications from OLEDs, bio-fluorescence imaging to sensor technologies and photonic energy storages roots on the enormous variety of organic materials. Especially in the field of metal- free aromatic designs, the range of possible materials showing diverse triplet harvesting effects is immense, making material development a highly complex task. Firstly, initial efforts in the understanding of the basic concepts behind TADF will be highlighted. A rational design strategy for TADF materials will be illustrated on an innovative material series based on phenylcarbazoles. A reasonable branch of isomers are theoretically constructed and slight stoichiometric modifications are performed to understand how molecular structure and intramolecular steric hindrance affects reverse intersystem crossing (RISC), while simultaneously revealing the strategy for deep blue TADF. The rational design of a bluish green TADF material called 5CzCF3Ph providing CIEy ≤ 0.4 is demonstrated, enabling peak EQE values of 12.1 % with a promising LT50 of 2 hrs at 500 cd∙m-2. Subsequently, the photophysics of five newly designed trimeric donor (D)-acceptor (A)-donor (D) type material compounds, analogue concepts to archetypical TADF designs, highlight the importance of intramolecular electronic couplings between adjacent triplet states for adiabatically-driven TADF, revealing the mechanism of local type triplet state perturbations on 3CT states. The most promising candidate (DMAC-PTO-DMAC) is disclosed and in turn optimized to meet required conditions for deep blue TADF emission. Ultimately, a deep blue luminescent material called isoDMAC-PTO is developed, featuring CIE coordinates of (0.16, 0.14) with an overall quantum yield of (86.4 ± 0.5) %. The focus switches to the fundamental understanding of the underlying mechanism giving rise to TADF in small molecules, leaving the scope of deep blue emission. While investigating the photophysical properties of a synthesized donor (D)-acceptor (A) type thermally activated delayed fluorescence (TADF) emitter named methyl 2-(9,9-dimethylacridin-10-yl)benzoate (DMAC-MB), it is possible to identify the excited state dynamics mediating the spin-flip process and hence the reutilization of non-radiative triplet states allowing for an internal quantum efficiency approaching unity. As experimentally observed by detailed temperature- and time-dependent transient photoluminescence (PL) measurements and consolidated by comprehensive quantum-chemical considerations, excited state configuration interaction by non-adiabatic couplings are anticipated as key property behind triplet up-conversion in the vicinity of conical intersections, contributing to recent research facing the exciton management within the auspicious field of TADF. For the first time, this thesis reports that even a TADF-silent molecule can be converted into efficient TADF systems by increasing the donor π- conjugation length through polymerization of the building block itself. With a total photoluminescence quantum yield up to 71 %, comprehensible research illustrates an efficient thermally activated delayed fluorescence polymer P1, based solely on non-TADF chromophores represented by a model compound 2 (PLQY of 3 % at RT). Finally, as predicted by TDDFT calculations and shown for the first time in the aspiring field of TADF, a thermally activated delayed fluorescence polymer based on a merely radiative, solely phosphorescent repeating unit is demonstrated. Intramolecular π-conjugation is exploited to trigger the charge-transfer excited state energy, revealing a general design tool to provoke TADF, reserved in particular for polymers. While the introduced twisted methyl 2-(9,9-dimethylacridin-10-yl) benzoate (DMAC-MB) reveals efficient thermally activated delayed fluorescence (TADF), a modified analogue 9,9-Dimethyl-5H,9H-quinolino[3,2,1-de]acridin-5-one (DMAC-ACR) shows emerging room temperature phosphorescence (RTP). As for TADF, intramolecular non-adiabatic couplings are unlocked as key feature actuating persistent RTP, linking photophysical analogies between TADF and RTP to structural self-similarities. Last but not least, degradation processes in TADF materials will be addressed. A correlation between theoretically calculated bond-dissociation energies (BDEs) and phenomenological observations reveals that low BDEs, in particular along pronounced charge-transfer bonds, ultimately lead to irreversible TADF material degradation induced by bi-molecular processes comprising TPQ as well as TTA. Finally, this thesis reveals the photophysics of 24 newly designed, synthesized and characterized TADF materials and demonstrates a fundamentally new approach for RTP, based on structural analogues to TADF. Far reaching design principles as conjugation induced TADF in polymers, as well as new design strategies selectively incorporating virbonic couplings yield device performances comprising LT50 of 2 hrs at 500 cd∙m-2 and targeted deep blue emission with CIE (0.16, 0.14). While lighting the way for TADF as future luminescent OLED materials, intrinsic material instabilities due to low bond-dissociation energies are disclosed as key-issues for tomorrows research.