Particles originating from bacteria, fungi (including mold spores, mildew, yeast), pollen, dust mites, and viruses can induce immune responses that trigger allergies and asthma. Carpeting is believed to act as a "sink" where bioparticulates are trapped via adhesive interactions and then are released by foot traffic or cleaning. This scenario can result in an accumulation of contaminants at higher levels than would be found outdoors or in a carpet-less environment. Numerous organizations (school districts, hospitals) have taken steps to remove carpeting, even though this hypothesis remains unproven. While statistical studies exist both in support and denial of the accumulation hypothesis, there is little fundamental understanding of the microscopic-level interactions between carpet and bioparticles. A fundamental understanding of particle affinities with polymers utilized in carpet would help to develop accurate models and address real problems in a rational and productive manner. In addition, a solution to the bioparticulate accumulation problem would have a profound impact on US health, resulting in significant economic savings. More than 20 million people suffer from asthma in the U.S., with children being the most vulnerable. In 2000 there were 9.3 million physician office visits and 1.8 million emergency room visits due to asthma alone, resulting in an estimated $9.4 billion in medical costs and $4.6 billion in lost productivity annually. In this thesis, two measurement techniques were developed to quantify the adhesive interactions between biological particulates and polymeric carpeting materials. Atomic force microscopy (AFM) was used to measure the adhesive interactions of relevant biological particulates (in this case the E. coli bacteria and A. artemisiifolia ragweed pollen grains) with Nylon-6 and Nylon-6,6, polyamide-12 and polystyrene. The adhesion force measurements were modeled using several adhesion theories. We found that the Hamaker models were sufficient for explaining the data, indicating the prominence of van der Waals forces in controlling bioparticle interactions with polyamides. In addition, the geometry of the pollen played a significant role: adhesion forces were approximately a multiple of the number of contact points the grain has with the surface. Forces for E. coli and polyamides were about the same magnitude as polyamide-polyamide surface self-interactions.

A study of which methods and measures that can be used to reduce fuel consumption and harmful discharges in an airline. The study begins with an investigation containing calculations of the differences between estimated fuel consumption calculated by a computer program called Skytrack and actual fuel consumption. Results from this study allows synchronization between actual consumption with calculated consumption. In addition to this methods and configurations to reduce weight and thus weight onboard aircrafts e.g. carpet exchange, lightweight trolleys and water reduction has been created and analysed. To bring the thesis to an end, the author has investigated other methods and configurations which TUIfly Nordic is implementing for fuel conservation. The thesis results in several conceivable areas for fuel conservation with calculated savings of 830 000 EUR which for the moment is implemented in TUIFly Nordic.

This thesis presents a historical analysis of literature through the intriguing (but often overlooked) overarching concepts of art –“das Mögliche”, “das Wirkliche” and “das Unmögliche”– and the changes in the historical orientations they represent. Each concept is demonstrated through the exploration of three key texts. The first text addressed in this thesis is Aristotle’s Poetics and the realm of the “Mögliche” he founded within his argument. The second concept, the “Wirkliche”, was inspired by the German Sturm und Drang writer J.M.R. Lenz and his text Anmerkungen übers Theater. Oscar Wilde’s dialogue “The Decay of Lying” summarizes the third and final concept discussed within this thesis, the “Unmögliche”. His desire for art to be unreal represents the accumulation of German Romantic thought and Oriental influence on Western Art. Through the contexts of these three categories and their texts we can obtain a more accurate understanding of the foundations and possibilities of art.

The catalytic depolymerization/pyrolysis of nylon 6 and 66 were investigated with the prospect of helping to curb the amount of carpet landfilled. Thermogravimetric analysis was used to determine which catalysts (and their nylon/catalyst ratio) were most suited for the depolymerization. By adding bases, the onset of degradation for some bases was 100 aC lower than that of the pure nylons. Potassium hydroxide and sodium hydroxide were found to be the most effective catalysts at a catalyst ratio of 100:1 of nylon 6 and nylon 66 to catalyst, respectively. After determining the most efficient catalyst, kinetic models/parameters from the TGA data were determined. These parameters were used in a reactive extrusion model for depolymerizing nylon 6 in carpet. Data from the model was then used to do cost analysis for the process. It was found that to get a Present Value Ratio greater than 1, the flow rate has to be greater than or equal to 500 lb/hr. At even higher flow rates up to the model¡¦s limit (1500 lb/hr), the Net Present Value shows that this process is economically viable. Extrusion of a 100:1 ratio of pure N6 and KOH was done in a 30 mm counter-rotating non-intermeshing twin screw extruder. The material collected from the vents of the extruder was tested with a gas chromatograph- mass spectrum (GC-MS) in tandem. There was only one significant peak from the GC and the primary molecular weight on the MS was 113, the molecular weight of caprolactam. This shows that the process could be profitable and require little purification if done industrially.

Motile cilia are hair-like cell appendages that actively bend themselves, thus driving the surrounding fluid in motion. For many microorganisms, such as unicellular Paramecium, cilia are essential for their motility. Higher animals, including mammals, utilize cilia for transporting fluids. For example, in humans, large collections of cilia, called cilia carpets, remove mucus and pathogens from the airways. Cilia constitute an example of biological oscillators that can spontaneously synchronize their beat in the form of metachronal waves, i.e., traveling waves of cilia phase. These waves may arise purely by hydrodynamic interactions between the cilia and supposedly enhance fluid transport. Our goal is to theoretically understand how the properties of individual cilia, e.g., cilia beat pattern, determine the emergent behavior, e.g., the direction of the metachronal wave. Additionally, we address the robustness of hydrodynamically-induced synchronization with respect to intrinsic active fluctuations of the cilia beat and disorder of intrinsic cilia frequencies. Both of these effects are not yet well understood. In this thesis, we studied metachronal synchronization in cilia carpets using a theoretical physicist’s toolbox. First, we proposed a novel multi-scale modeling framework Lagrangian Mechanics of Active Systems (LAMAS) to describe fluid-structure interactions for active elastic structures, such as cilia. We quantified hydrodynamic interactions between cilia using detailed hydrodynamic simulations with a realistic cilia beat pattern. In the dynamical simulations for N = 2 cilia, we found that cilia would synchronize either in-phase or anti-phase, depending on their relative positions. For a lattice of N ≫ 1 cilia, we found the emergence of metachronal waves, many of which are locally stable. Nevertheless, just a single wave has a predominantly large basin of attraction, i.e., it is likely to be selected from a random initial condition. In the presence of noise, synchronization abruptly breaks up beyond a characteristic noise strength. Likewise, for cilia with non-identical intrinsic frequencies, synchronization is lost beyond a characteristic level of frequency disorder. In large cilia carpets, noise excites long-wavelength perturbations, whose relaxation times are proportional to the square of the system length. Thus, in large systems, we predict locally synchronized domains, instead of the global synchronization.

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Les travaux réalisés dans le cadre de cette thèse ont porté sur la réalisation de matériaux composites nanostructurés à base de nanotubes de carbone verticalement alignés (NTC alignés) et de polymères π-conjugués en vue de leur utilisation en tant que matériaux d’électrodes dans des dispositifs de stockage d’énergie de type supercondensateurs. Dans une première partie, les travaux se sont focalisés sur la croissance par CVD d’aérosol de NTC sur des substrats d’acier inoxydable via le dépôt préalable d’une sous-couche céramique SiOx. Grâce à l’optimisation de ce procédé, des tapis de NTC longs, denses et alignés pouvant directement servir de supports à l’électrodépôt de polymères π-conjugués ont pu être obtenus. Dans une seconde partie, les travaux se sont concentrés sur l’électrodépôt de poly(3-méthylthiophène) (P3MT) en milieu liquide ionique EMITFSI sur les tapis de NTC alignés à partir d’une méthode chronopotentiométrique « séquencée » permettant de réaliser des dépôts homogènes dans la profondeur des tapis. Une composition massique optimale de 70 % de P3MT permettant d’atteindre des capacitances spécifiques de 170 F.g-1 de polymère tout en conservant des cinétiques de charge-décharges élevées, comparativement à des composites NTC/P3MT enchevêtrés, a pu être déterminée. A partir des matériaux composites optimisés, des dispositifs symétriques NTC/P3MT // P3MT/NTC et hybrides CA // P3MT/NTC ont été assemblés. Le dispositif hybride à notamment permis d’atteindre une tension de 2,7 V et une capacitance de système de 26 F.g-1 en milieu EMITFSI à 25 °C. Par ailleurs, une énergie maximale de 23 Wh.kg-1 et une puissance maximale de 6,9 kW.kg-1 ont été obtenues avec une perte de seulement 7 % après 4000 cycles. Pour finir, l’électrodépôt de polypyrrole (Ppy) a été étudié dans différents milieux liquides ioniques protiques et aprotiques. Après des études réalisées par microbalance à cristal de quartz permettant de mieux comprendre les mécanismes d’insertion des espèces ioniques lors de la croissance du polymère conjugué et lors de son dopage positif réversible, des dépôt de Ppy ont été réalisés et optimisés dans la profondeur des tapis de NTC alignés. Des nanocomposites NTC alignés/Ppy présentant des capacitances spécifiques comprises entre 100 et 130 F.g-1 ont ainsi pu être obtenus. / This thesis focused on the elaboration of nanostructured composite materials based on vertically aligned carbon nanotubes (aligned CNT) and π-conjugated polymers and their use as electrode materials in supercapacitor-type energy storage devices. The first part focused on aligned CNT growth by aerosol-assisted CVD on stainless steel substrates and the deposition of a SiOx ceramic sublayer. Thanks to the optimization of this growth process, long, dense, and aligned CNT carpets which can directly act as support for the electrodeposition of π-conjugated polymers were obtained. The second part focused on the electrodeposition of poly (3-methylthiophene) (P3MT) in EMITFSI ionic liquid medium on aligned CNT carpets using a “pulsed” chronopotentiometric method to produce homogeneous deposits in the depth of the carpets. An optimal P3MT mass composition of 70 %, which helped achieve a specific capacitance of 170 F.g-1 of polymer while maintaining high charge-discharge kinetics, compared with NTC/P3MT entangled composites, was determined. NTC/P3MT // P3MT/NTC symmetrical devices and CA // P3MT/NTC hybrid devices were assembled using the optimized composite materials. The hybrid device reached a voltage of 2.7 V and a system capacitance of 26 F.g-1 in EMITFSI at 25 ° C. Furthermore, a maximum energy of 23 Wh.kg-1 and a maximum power of 6.9 kW.kg-1 were obtained with only a 7 % loss after 4000 cycles. Finally, the electrodeposition of polypyrrole (Ppy) was investigated in different protic and aprotic ionic liquids. After quartz crystal microbalance studies in order to better understand the insertion mechanisms of ionic species during conjugated polymer growth and during its reversible positive doping, the electrodeposition of Ppy within the deepness of the aligned CNT carpets was optimized. Aligned CNT/Ppy nanocomposites with specific capacitances ranging between 100 and 130 F.g-1 were obtained.

The following work examines how childhood ornaments and memories can be translated into the material world, particularly through graphic design. This process not only creates a beautiful symbol of childhood but also offers a reflection in adulthood.