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.

Um die Leistung und Lebensdauer von energietechnischen Komponenten weiter zu steigern, sind höhere Leistungen, Leistungsdichten sowie Prozesswirkungsgrade zentrale Bestandteile künftiger Entwicklungen. Mit steigernden Leistungsdichten erhöhen sich auch stetig die Belastungen der einzelnen Komponenten. Zusammen mit neuen Werkstoffen und technologischem Fortschritt, wie beispielsweise verbesserten Kühltechnologien oder strömungstechnischen Optimierungen ermöglicht auch eine verbesserte Kenntnis der Belastungsbedingungen und des Schädigungsverhaltens höhere Leistungen und Leistungsdichten. Aktuelle Gasturbinen und oft auch Kraftwerkskomponenten unterliegen zusätzlich zu den mechanischen und zeitlich variablen thermischen Beanspruchungen auch großen örtlichen thermischen Gradienten, die die Lebensdauer der Komponenten stark beeinflussen. Diese thermischen Gradienten induzieren zum einen zusätzliche Beanspruchungen und die örtlich variablen Temperaturfelder führen zum anderen zu stark variierenden Werkstofffestigkeiten. In dieser Arbeit wird ein Prüfstand zur realistischen Prüfung eines typischen Gasturbinenschaufelmaterials Mar-M247 entwickelt und mit diesem eine systematische experimentelle Untersuchung des Einflusses thermischer Gradienten auf die niederzyklische Ermüdungsfestigkeit unter erhöhten Temperaturen durchgeführt. Im weiteren Teil der Arbeit wird ein visko-elasto-plastisches Materialmodell weiterentwickelt, um die lokal unsymmetrische Beanspruchung der Proben unter zyklischer Last realistisch abbilden zu können. Mit Hilfe von Experimenten aus der Literatur werden dabei zunächst die Grenzen und Möglichkeiten des Modells diskutiert, um es dann auf den konkreten Werkstoff anzupassen. Der wesentliche Vorteil des entwickelten Modells liegt in der verbesserten Beschreibung des zyklischen Kriechens und zyklischen Relaxierens (Ratcheting) insbesondere unter einachsiger Beanspruchung und in der nachträglichen Anpassungsmöglichkeit des spezifischen Ratchetingterms nach der Anpassung aller anderen Materialparameter. Die Analyse der experimentell ermittelten Lebensdauern erfolgt sowohl mit ingenieurmäßigen Methoden basierend auf der spannungsabhängigen Lebensdauerbeschreibung nach Basquinund Wöhler als auch mittels eines lokalen bruchmechanischen Ansatzes, der es ermöglicht,sowohl die Rissinitiierung als auch den Rissfortschritt unter variabler Temperatur und kombinierter Kriech- und Ermüdungsbeanspruchung zu beschreiben. Das Material- und Lebensdauermodell werden zusammen im letzten Teil der Arbeit eingesetzt, um das Verformungs- und Lebensdauerverhalten der untersuchten Proben zu berechnenund es kann gezeigt werden, dass sich die Versuche mit sehr guter Qualität wiedergeben lassen.:Versicherung i Abstract iii Kurzfassung v List of abbreviations and symbols xi 1 Introduction 1 2 Objective 5 3 State of the art 7 3.1 Thermal and mechanical loading of gas turbine components . . . . . . . . . . 7 3.2 Material characterisation of nickel-based superalloys . . . . . . . . . . . . . . 9 3.3 Deformation modelling based on constitutive material laws . . . . . . . . . . 13 3.3.1 Ramberg-Osgood material law . . . . . . . . . . . . . . . . . . . . . . 13 3.3.2 Strain and stress tensor . . . . . . . . . . . . . . . . . . . . . . . . . . 14 3.3.3 Thermodynamic principles . . . . . . . . . . . . . . . . . . . . . . . . 14 3.4 Elasto-visco-plastic material models . . . . . . . . . . . . . . . . . . . . . . . 15 3.4.1 Isotropic hardening . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 3.4.2 Kinematic hardening . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 3.4.3 Kinematic hardening for improved simulation of ratcheting . . . . . . 18 3.4.4 Viscosity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 3.5 Failure at elevated temperatures . . . . . . . . . . . . . . . . . . . . . . . . . 22 3.5.1 Fundamental fatigue life models . . . . . . . . . . . . . . . . . . . . . 24 3.5.2 Creep . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 3.5.3 Crack growth models for fatigue loading . . . . . . . . . . . . . . . . . 28 3.5.4 Creep crack growth based on C(t) and C ∗ . . . . . . . . . . . . . . . . 33 3.5.5 Temperature dependency and normalization methods . . . . . . . . . 35 3.5.6 Lifetime under temperature variation . . . . . . . . . . . . . . . . . . . 37 3.5.7 Influence of mean stresses on lifetime . . . . . . . . . . . . . . . . . . . 38 3.5.8 Influence of oxidation on failure at elevated temperatures . . . . . . . 42 3.5.9 Constitutive damage and crack growth models . . . . . . . . . . . . . 45 3.6 Experimental methods for the generation of large homogeneously distributed heat flux densities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51 3.6.1 Resistance heating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51 3.6.2 Inductive heating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 3.6.3 Convective heating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 3.6.4 Laser based heating . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54 3.6.5 Radiation heating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54 3.7 Conclusion on the state of the art . . . . . . . . . . . . . . . . . . . . . . . . . 56 4 Development of a test system for cyclic fatigue tests under homogeneous surface temperature conditions 59 4.1 Boundary conditions for the development . . . . . . . . . . . . . . . . . . . . 59 4.2 Concept for a test system with a new highly focusing heating . . . . . . . . . 60 4.2.1 Simulation of heat fluxes of different furnace geometries by ray-tracing 60 4.3 Definition of reflection and transmission coefficient . . . . . . . . . . . . . . . 64 4.3.1 Simulation of the radiation behaviour for the furnace concepts . . . . 66 4.4 Analytical calculation of heat transfer inside the hollow specimen . . . . . . . 71 4.5 Finite element calculation of temperature distribution in the specimen wall . 73 4.6 Design and evaluation of the specimen internal cooling system . . . . . . . . . 75 4.6.1 Installation of heating and development of the load train . . . . . . . 81 5 Experimental investigation 85 5.1 Measurement of surface temperatures and thermal gradients . . . . . . . . . . 87 5.1.1 Measurement of surface temperature . . . . . . . . . . . . . . . . . . . 87 5.1.2 Axial surface temperature distribution . . . . . . . . . . . . . . . . . . 90 5.1.3 Measurement of thermal gradients across specimen wall . . . . . . . . 92 5.2 Results of isothermal ratcheting tests . . . . . . . . . . . . . . . . . . . . . . . 96 5.3 Deformation behaviour of cyclic tests with superimposed thermal gradients . 98 5.3.1 Variation of mean strain and mean stress . . . . . . . . . . . . . . . . 98 5.4 Termination criteria for the tests . . . . . . . . . . . . . . . . . . . . . . . . . 100 5.4.1 Measurement of modulus of elasticity . . . . . . . . . . . . . . . . . . 101 5.5 Low cycle fatigue life of Mar-M247 with and without superimposed thermal gradient . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104 5.6 Results of hollow cylindrical specimen testing with thermal gradients . . . . . 108 6 Microstructural investigation 113 7 Deformation modeling with improved ratcheting simulation based on small scale strain theory 123 7.1 Modeling of ratcheting behaviour of Mar-M247 . . . . . . . . . . . . . . . . 123 7.1.1 Improvement of uniaxial ratcheting description for the Armstrong- Frederick-model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124 7.1.2 Evaluation of the proposed model for multiaxiality . . . . . . . . . . . 129 7.2 Application of the deformation model on Mar-M247 . . . . . . . . . . . . . 132 8 Lifetime calculation of the nickel-base-superalloy Mar-M247 based on engineering and crack growth methods 139 8.1 Modification of the Krämer crack growth model . . . . . . . . . . . . . . . . 139 8.2 Choice of basic variable for the fatigue crack growth and crack initiation . . . 140 8.3 Oxidation based crack growth model . . . . . . . . . . . . . . . . . . . . . . . 142 8.4 Creep crack growth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148 8.5 Creep . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149 8.6 Fatigue life . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152 8.6.1 Extension of the Paris crack growth model based on intrinsic defect size152 8.6.2 Crack length independent formulation of J-integral . . . . . . . . . . . 154 8.7 Combined model for comprehensive description of the crack-initiation and -growth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156 8.7.1 Comparison to crack growth experiments . . . . . . . . . . . . . . . . 161 8.7.2 Comparison to fatigue experiments . . . . . . . . . . . . . . . . . . . . 164 9 Application of material and crack growth model to the experiments with superimposed thermal gradient 167 9.1 Geometry function for the hollow specimen investigated . . . . . . . . . . . . 167 9.2 Application of the crack growth model on non-isothermal tests . . . . . . . . 170 9.2.1 Calculation of the stress strain field of hollow cylindrical specimen subjected to thermally induced stress gradients with the elasto-visco- plastic model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 172 9.2.2 Calculated crack growth behaviour under locally non-isothermal con- ditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176 10 Conclusion and outlook 181 Bibliography 185

Today there is growing interest within the construction sector to increase the proportion of biobased building materials made from renewable resources. By-products or residuals from wood processing could in this case be valuable resources for manufacturing new types of biocomposites. An important research question related to wood-based biocomposites is how to characterise molecular interactions between the different components in the composite. The hygroscopic character of wood and its water sorption properties are also crucial. Thermal modification (or heat treatment) of wood results in a number of enhanced properties such as reduced hygroscopicity and improved dimensional stability as well as increased resistance to microbiological decay. In this thesis, surface characteristics of thermally modified wood components (often called wood fibres or particles) and influencing effects from moisture sorption have been analysed using a number of material characterisation techniques. The aim is to increase the understanding in how to design efficient material combinations for the use of such wood components in biocomposites. The specific objective was to study surface energy characteristics of thermally modified spruce (Picea abies Karst.) under influences of water vapour sorption. An effort was also made to establish a link between surface energy and surface chemical composition. The surface energy of both thermally modified and unmodified wood components were studied at different surface coverages using inverse gas chromatography (IGC), providing information about the heterogeneity of the surface energy. The water vapour sorption behaviour of the wood components was studied using the dynamic vapour sorption (DVS) method, and their surface chemical composition was studied by means of X-ray photoelectron spectroscopy (XPS). Additionally, the morphology of the wood components was studied with scanning electron microscopy (SEM). The IGC analysis indicated a more heterogeneous surface energy character of the thermally modified wood compared with the unmodified wood. An increase of the dispersive surface energy due to exposure to an increased relative humidity (RH) from 0% to 75% RH at 30 ˚C was also indicated for the modified samples. The DVS analysis indicated an increase in equilibrium moisture content (EMC) in adsorption due to the exposure to 75% RH. Furthermore, the XPS results indicated a decrease of extractable and a relative increase of non-extractable compounds due to the exposure, valid for both the modified and the unmodified wood. The property changes due to the increased RH condition and also due to the thermal modification are suggested to be related to alterations in the amount of accessible hydroxyl groups in the wood surface. Recommendations for future work and implications of the results could be related to knowledge-based tailoring of new compatible and durable material combinations, for example when using thermally modified wood components in new types of biocomposites for outdoor applications. / <p>Forskningsfinansiärer och strategiska forskningsprojekt:</p><p>Nils och Dorthi Troëdssons forskningsfond (Projektnr 793/12 Hydro-termo-mekanisk modifiering av trä).</p><p> KTH Royal Institute of Technology.</p><p> COST Action FP0904.</p><p> KK-Stiftelsen.</p><p>Stiftelsen för strategiskt forskning (SSF). QC 20150908</p>

Kohlenstoff 2D-Nanoschichten wie Graphen und Graphenoxid sind vielversprechend, aber schwierig in Bezug auf multivalente Wechselwirkungen zu kontrollieren. Das Verständnis, wie neuartige Funktionalisierungsmethoden die Geometrie, Wechselwirkungen und elektronischen Eigenschaften der Graphenblätter beeinflussen, ist der Schwerpunkt dieser Arbeit. Diese Arbeit untersucht zwei Methoden zur Modifikation von 2D-Graphennanoschichten: "Graft to" und "Graft from" Techniken, unter Verwendung von „[2+1] Nitren-Cycloaddition“ und ringöffnender Polymerisation von Glycerin, zusätzlich zum Wachstum von 2D-Triazin-Kohlenstoffstrukturen. Diese modifizierten Nanoschichten wurden hinsichtlich ihrer Wechselwirkung mit dem Vesikulären Stomatitis-Virus (VSV) und ihrer Zweidimensionalität mittels Rastersondenmikroskopie und Raman-Spektroskopie untersucht. Die Studie zeigt das Potenzial funktionalisierter Graphen in der Virologie und liefert Einblicke für zukünftige Forschungen. Ergebnisse zeigten, dass funktionalisierte 2D-TRGO an VSV-Partikel bindet und flexibel genug bleibt, um auf einer flachen Glimmeroberfläche Falten zu bilden, aber sie können die Virushüllen nicht vollständig umschließen. Dies liegt an den hohen Energiekosten für das Biegen großer lateraler Dimensionen (~1-2 μm) im Vergleich zur 200 nm Länge der VSV-Partikel. Eine optimale laterale Dimension von ~300 nm für funktionalisierte 2D-TRGO-Blätter maximiert virale Wechselwirkungen, Hemmungseffizienz und Anzeichen viraler Umhüllung. Triazin, ein Schlüsselmolekül in der Funktionalisierung, kann zur Herstellung von 2D-Triazin-Strukturen im Gramm-Maßstab verwendet werden. Potenzielle Anwendungen funktionalisierter Graphene umfassen spezialisierte antivirale Therapien und die Verwendung als Plattform für antivirale Medikamente. Zudem zeigten die Ergebnisse minimale Störungen der elektronischen Struktur von Graphen durch Triazin-Funktionalisierung. / Carbon-based 2D nanosheets like graphene and graphene oxide are promising but challenging to control in terms of multivalent interactions. Understanding how novel functionalization methods affect graphene sheets' geometry, interaction specificity and electronic properties is the focus of this thesis, which is crucial for advancing the design of 2D nanomaterials. This thesis examines two novel methods for modifying 2D graphene nanosheets: "graft to" and "graft from" techniques, using [2+1] nitrene cycloaddition reactions and ring-opening multibranch polymerization of glycerol in addition to in plane growth of 2D triazine -carbon based structures. These modified nanosheets were studied for their interaction with vesicular stomatitis virus (VSV) and their two-dimensionality using scanning probe microscopy methods and Raman spectroscopy. The study highlights the potential of functionalized graphene nanosheets in virology and provides insights for future research. Results revealed that functionalized 2D TRGO binds to VSV particles and remains flexible enough to wrinkle on a flat mica interface but they cannot completely wrap the viral envelopes. This is due to the high energy cost of bending large lateral dimensions (~1-2μm) compared to the 200 nm length of VSV particles. An optimum lateral dimension of ~300 nm for functionalized 2D TRGO sheets was found to maximize viral interactions, inhibition efficiency, and signs of viral envelopment. Triazine, a key molecule in functionalization, can also be used to create 2D triazine structures on a gram scale. Functionalized graphene's potential applications include specialized antiviral therapies, such as targeted therapies exploiting multivalent interactions between viruses and cellular receptors, and using functionalized graphene as a delivery platform for antiviral drugs. Additionally, results showed minimal disturbance of graphene electronic structure via Triazine functionalization.

A new method, probability distribution of diffusivities (time scaled square displacements between succeeding video frames), was developed to analyze single molecule tracking (SMT) experiments. This method was then applied to SMT experiments on ultrathin liquid tetrakis(2-ethylhexoxy)silane (TEHOS) films on Si wafer with 100 nm thermally grown oxide, and on thin semectic liquid crystal films. Spatial maps of diffusivities from SMT experiments on 220 nm thick semectic liquid crystal films reveal structure related dynamics. The SMT experiments on ultrathin TEHOS films were complemented by fluorescence correlation spectroscopy (FCS). The observed strongly heterogeneous single molecule dynamics within those films can be explained by a three-layer model consisting of (i) dye molecules adsorbed to the substrate, (ii) slowly diffusing molecules in the laterally heterogeneous near-surface region of 1 - 2 molecular diameters, and (iii) freely diffusing dye molecules in the upper region of the film. FCS and SMT experiments reveal a strong influence of substrate heterogeneity on SM dynamics. Thereby chemisorption to substrate surface silanols plays an important role. Vertical mean first passage times (mfpt) in those films are below 1 µs. This appears as fast component in FCS autocorrelation curves, which further contain a contribution from lateral diffusion and from adsorption events. Therefore, the FCS curves are approximated by a tri-component function, which contains an exponential term related to the mfpt, the correlation function for translational diffusion and a stretched exponential term for the broad distribution of adsorption events. Lateral diffusion coefficients obtained by FCS on 10 nm thick TEHOS films, thereby, are effective diffusion coefficients from dye transients in the focal area. They strongly depend on the substrate heterogeneity. Variation of the frame times for the acquisition of SMT experiments in steps of 20 ms from 20 ms to 200 ms revealed a strong dependence of the corresponding probability distributions of diffusivities on time, in particular in the range between 20 ms and 100 ms. This points to average dwell times of the dye molecules in at least one type of the heterogeneous regions (e.g. on and above silanol clusters) in the range of few tens of milliseconds. Furthermore, time series of SM spectra from Nile Red in 25 nm thick poly-n-alkyl-methacrylate (PnAMA) films were studied. In analogy to translational diffusion, spectral diffusion (shifts in energetic positions of SM spectra) can be studied by probability distributions of spectral diffusivities, i.e. time scaled square energetic displacements. Simulations were run and analyzed to study contributions from noise and fitting uncertainty to spectral diffusion. Furthermore the effect of spectral jumps during acquisition of a SM spectrum was investigated. Probability distributions of spectral diffusivites of Nile Red probing vitreous PnAMA films reveal a two-level system. In contrast, such probability distributions obtained from Nile Red within a 25 nm thick poly-n-butylmethacrylate film around glass transition and in the melt state, display larger spectral jumps. Moreover, for longer alkyl side chains a solvent shift to higher energies is observed, which supports the idea of nanophase separation within those polymers.

A new method, probability distribution of diffusivities (time scaled square displacements between succeeding video frames), was developed to analyze single molecule tracking (SMT) experiments. This method was then applied to SMT experiments on ultrathin liquid tetrakis(2-ethylhexoxy)silane (TEHOS) films on Si wafer with 100 nm thermally grown oxide, and on thin semectic liquid crystal films. Spatial maps of diffusivities from SMT experiments on 220 nm thick semectic liquid crystal films reveal structure related dynamics. The SMT experiments on ultrathin TEHOS films were complemented by fluorescence correlation spectroscopy (FCS). The observed strongly heterogeneous single molecule dynamics within those films can be explained by a three-layer model consisting of (i) dye molecules adsorbed to the substrate, (ii) slowly diffusing molecules in the laterally heterogeneous near-surface region of 1 - 2 molecular diameters, and (iii) freely diffusing dye molecules in the upper region of the film. FCS and SMT experiments reveal a strong influence of substrate heterogeneity on SM dynamics. Thereby chemisorption to substrate surface silanols plays an important role. Vertical mean first passage times (mfpt) in those films are below 1 µs. This appears as fast component in FCS autocorrelation curves, which further contain a contribution from lateral diffusion and from adsorption events. Therefore, the FCS curves are approximated by a tri-component function, which contains an exponential term related to the mfpt, the correlation function for translational diffusion and a stretched exponential term for the broad distribution of adsorption events. Lateral diffusion coefficients obtained by FCS on 10 nm thick TEHOS films, thereby, are effective diffusion coefficients from dye transients in the focal area. They strongly depend on the substrate heterogeneity. Variation of the frame times for the acquisition of SMT experiments in steps of 20 ms from 20 ms to 200 ms revealed a strong dependence of the corresponding probability distributions of diffusivities on time, in particular in the range between 20 ms and 100 ms. This points to average dwell times of the dye molecules in at least one type of the heterogeneous regions (e.g. on and above silanol clusters) in the range of few tens of milliseconds. Furthermore, time series of SM spectra from Nile Red in 25 nm thick poly-n-alkyl-methacrylate (PnAMA) films were studied. In analogy to translational diffusion, spectral diffusion (shifts in energetic positions of SM spectra) can be studied by probability distributions of spectral diffusivities, i.e. time scaled square energetic displacements. Simulations were run and analyzed to study contributions from noise and fitting uncertainty to spectral diffusion. Furthermore the effect of spectral jumps during acquisition of a SM spectrum was investigated. Probability distributions of spectral diffusivites of Nile Red probing vitreous PnAMA films reveal a two-level system. In contrast, such probability distributions obtained from Nile Red within a 25 nm thick poly-n-butylmethacrylate film around glass transition and in the melt state, display larger spectral jumps. Moreover, for longer alkyl side chains a solvent shift to higher energies is observed, which supports the idea of nanophase separation within those polymers.