Conjugated polymers have attracted much interest as promising alternatives to inorganic semiconductors, due to their low-temperature, solution-based processability, which may provide for low-cost, large-area electronic device fabrication. However, commercialization of polymer-based electronic devices has been restricted owing to low device performance of solidified thin-films. In order to enhance charge transport of polymer semiconductor thin-films, the self-organization of organic polymer semiconductors into ordered supramolecular assemblies has been achieved by tuning a range of process parameters including film deposition method (spin vs. drop cast), solvent boiling point (low vs. high boiling point), polymer-dielectric interface treatment, and post-deposition processing (solvent vapor or thermal annealing). However, these strategies give rise to limitations for large-scale high-throughput processing due to associated pre- and/or post semiconductor deposition steps. Therefore, in this thesis, we identify alternative processing parameters (i.e., hydrogen bonds between good and poor solvents, UV irradiation to polymer precursor solutions, and combination of sonication and subsequent UV irradiation to polymer precursor solutions) which can contribute to enhancement in charge transport of a model polymer semiconductor, poly(3-hexylthiophene) (P3HT), eliminating the additional pre- and/or post-steps mentioned above. Further, we understand of how the processing parameters effect intra- and intermolecular interactions of the polymer chains, micro- through macroscopic morphologies, and charge transport characteristics of the resultant films.

Three batches of milk were ultrafiltered to 60, 65, or 70% volume reduction before diafiltration. Starting diafiltration at 70% volume reduction took less time and water without affecting nutrient recovery. Whole milk was heated to 60, 72, and 82°C for 16 s. Milk representing each heat treatment was divided into three batches, one unacidified (pH 6.6), the others acidified to pH 6.2 and 5.8. The milk was ultrafiltered, diafiltered, and concentrated to 5x (80% volume reduction). Retentate was inoculated with .5% lactic culture and incubated at 28°C to pH 5.1. Each lot of fermented retentate was evaporated under 76 kPa vacuum until moisture was reduced to 35-38%, then made into pasteurized process cheese food by cooking to 82°C. The final product contained 43-44% moisture, 24-28% fat, 1.7% salt, and 2.5% sodium citrate. Fat and protein recovery were not affected by heat treatment or pH adjustment of the milk. Recovery of calcium, phosphorus, and riboflavin were significantly reduced following acidification of milk. Riboflavin recovery was higher when milk was preheated to 60°C as opposed to 72 or 82°C. Effect of cooking temperature on meltability of process cheese food was evaluated by repeating the above experiment at three cooking temperatures, 70, 76, or 81 °C. Cooking temperature significantly affected meltability. Cheese cooked to 70°C melted best for all treatments. At all cooking temperatures, cheese from unacidified milk (pH 6.6) had greater meltability than cheese from milk acidified to pH 5.8 or 6.2. Cooking temperature had a greater effect on meltability of process cheese food made from ultrafiltered retentate than calcium content. Preheating milk before ultrafiltration did not significantly affect meltability of pasteurized process cheese food. Meltability of pasteurized process cheese food was best when made from retentate heated (following ultrafiltration) to 61°C for 16 sand poorest when retentate was heated to 72 or 83°C. During ultrafiltration without diafiltration, amino acid analysis was on samples taken at 0, 20, 40, 60, and 80% volume reduction. There were no differences in amino acid composition (g/100 g protein) between milk and 5x retentate. Soluble nitrogen at pH 4.6 in pasteurized process cheese food was an approximate measure of undenatgred whey protein. As processing temperature increased from 66 to 82°C, undenatured whey protein decreased. Decrease in meltability due to increased processing temperature was related to denaturation of whey protein. Process cheese food made from blends of UF curd and Cheddar cheese had acceptable meltability with up to 66% UF curd when the final processing temperature was 68°C. Milk with high bacterial numbers (7.8 x 106 CFU/ml) was heated to 72°C for 16 s, acidified to pH 5.8 and ultrafiltered to a 5x concentration. Ultrafiltration proceeded normally and no processing difficulties were encountered.

In the past two decades, the number of observations and the accuracy of satellite-basedgeodetic measurements like Global Navigation satellite systems (GNSS) greatly increased,providing measured values of displacements and velocities of permanent geodetic stations.Establishment of the geodetic control networks and collecting geodetic observations, indifferent epochs, are a commonly used method for detection of displacements andconsequently disaster management. Selecting proper processing parameters for differenttypes of monitoring networks are critical factors of the deformation monitoring analysisusing GNSS, which is the main aim of this research. In this study, a simulation study and acontrolled survey were performed using simultaneous GNSS measurements of 5 geodeticpillars, established by Lantmäteriet at Gävle airport. Sensitivity analyses were performed ondifferent types of monitoring networks using different set of processing paarameters . Thesescenarios consider different sets of parameters, different types of monitoring networks, andvarious number of monitoring stations to evaluate the detectable displacements andcompare with the known millimeter displacements (simulated one). The results showed thatthe selection of processing parameters depends on the type and size of the monitoringnetwork and the location of the monitoring stations. Analyses also show that onlineprocessing services can provide mm-cm level accuracy for displacement detection ifsufficient observation time is available. Finally, checks were performed on the two ofsample scenarios to find the minimum observation time required for reaching to the mostaccurate simulated (preset) displacements.

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La polyaniline est un polymère conducteur intrinsèque aux potentialités indéniables dans le domaine de la micro-électronique. Elle allie la légèreté, le faible coût et la modularité des polymères avec les propriétés de conduction électrique des métaux. La mise à profit de ce mélange de propriétés à l’échelle industrielle nécessite une maitrise des procédés de mise en œuvre de la polyaniline, notamment sous forme de film polymère, domaine où il y a encore un manque de maitrise. Pour y remédier, il faudrait tout d’abord comprendre l’influence de chaque paramètre de mise en œuvre sur les propriétés de conduction du film de polyaniline. Pour cela, nous avons choisi une polyaniline plast-dopée commerciale à l’état de dispersion et avons fait une étude paramétrique sur l’effet du type de solvant utilisé pour la dispersion ainsi que celui de la température d’évaporation de celui-ci lors du dépôt du film. Deux types d’études ont été menés : la première porte sur les propriétés rhéologiques et diélectriques des dispersions de polyaniline et la seconde sur les propriétés structurales et de conduction des films. A travers la première étude, nous avons pu montré que lors du chauffage des dispersions de polyaniline, celles-ci subissaient une transition structurale liquide-liquide du second ordre dont les paramètres varient avec le type du solvant utilisé. A travers la seconde étude, nous avons aussi mis en évidence que les films déposés dans les domaines avoisinant la température transition de phase dans les mélanges liquides sont les moins conducteurs et les moins cristallisés. Selon le type de solvant choisi, deux mécanismes de conduction ont été trouvés : les sauts à portées variables tridimensionnel (VRH 3D), pour le cas de la série de films issus de la dispersion dans l’acide dichloroacétique et déplacement par effet tunnel induit par les fluctuations thermiques (FIT) pour la série de films issus de la dispersion dans le mélange acide dichloroacétique / acide formique. Il en ressort finalement que pour obtenir un film de polyaniline plast-dopée ayant la conductivité la plus élevée, il faut appliquer les conditions expérimentales qui permettent d’obtenir un degré de cristallinité élevé (298 K pour PANI/DCAA). / The purpose of this study is to perform polyaniline films with the highest conductivity. The effect of the solvent type and the casting temperature on the electrical properties of plastdoped polyaniline dispersions and films were investigated. For this purpose, rheological and dielectric investigations have been undertaken for dispersions of plast-doped polyaniline in two different solvents (dichloroacetic acid and formic acid / dichloroacetic acid mixture). Changes appearing above a certain temperature, 318K for PANI/DCAA and 313K for PANI/DCAA-FA, for both rheological dielectric and rheological parameters revealed the existence of a second order liquid-liquid structural transition occurring in the polyaniline organic dispersions. We also investigated the effect of the selected processing parameters on the film properties. We found that the DC conductivity mechanism is governed by Mott’s three-dimensional variable range hopping (3D VRH) model for PANI/DCAA films and by a fluctuation induced tunnelling model (FIT) for PANI/DCAA-FA films. Besides, the films cast at temperatures around the second order liquid-liquid structural transition temperature of polyaniline dispersions lead to the lowest conductivity and crystallinity, regardless of the solvent type used. A qualitative correlation was also found between the conductivity and the crystallinity of the polyaniline films. So, in order to obtain films with the highest electric conductivities, we have to apply experimental conditions leading to the highest crystallinity (298 K for PANI/DCAA).

No / The advances of the polymer melt flow-induced crystallization behaviour and its influence on mechanical properties of high density polyethylene (HDPE) in micron injection (MI) were studied in the present paper. Analysis of mechanical performance, including yield stress and elongation at break, for samples adopted from different regions in a molded plaque showed that a higher injection speed, a higher mold temperature and a longer cooling time could effectively enhance the yield stress but negatively promoted the ductility. Then, the mechanisms of such variation of mechanical performance and the factors affecting it were investigated by means of differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and polarized light microscopy (PLM). The super high shear rate during cavity feeding in MI molding not only induced a typical three-layered structure but also developed a highly oriented fibrously morphological structure in the skin layer. However, such fully oriented morphology was much negative in the interlayer and even could not be observed in the core layer. The results from SEM and PLM observations indicated that the orientation morphology varied significantly through the plaque's cross-section and thickness of the each layer changed with the process parameters and geometric position, and finally led to variation of the mechanical performance.