In this Thesis, the structure of thin films formed by a conducting polymer, polyaniline, was studied using mainly infrared and Raman spectroscopies. That led to the study of aniline oligomers. The oligomers play a key role in the formation of thin films and nanostructures of polyaniline. Furthermore, the Thesis deals with the carbonization of various forms of polyaniline (granular polyaniline base, thin films of polyaniline salt, multi-wall carbon nanotubes coated with polyaniline salt or base, polyaniline nanotubes/nanorods prepared in the presence of ethanol). The two topics, aniline oligomers and carbonization of polyaniline, are connected by a paper concerning the carbonization of microspheres formed during oxidation of aniline in alkaline medium. Optical microscopy, transmission and scanning electron microscopy, UV-Vis spectroscopy, spectroscopic ellipsometry, wide angle X-ray scattering and thermogravimetric analysis were used.

Water pollution represents one of the major concerns of the modern world, after scientific and industrial development that generates hazardous organic and inorganic contaminants. Biochar (BC) has gained tremendous attention in the past decade as a cheap and efficient adsorbent for organic and inorganic contaminants from aqueous solutions. BC is considered to be a low-cost alternative to activated carbon, however, BC typically suffer performance reductions due to their low surface areas and poor mechanical properties. The main objective of this work is to develop novel biochar materials by modifying the biochar surface for the removal of organic and inorganic contaminants from water. In recent years, biochar modifications involving various methods such as, acid/base treatment, impregnation of mineral sorbents, functional groups incorporation, steam activation and magnetic modification have been widely studied. Chapter I summarizes these biochar modification methods. In Chapter II, Chitosan-Modified fast pyrolysis BioChar (CMBC) was used to remove Pb2+ from water. CMBC was made by mixing pine wood biochar with a 2% aqueous acetic acid chitosan (85% deacylated chitin) solution followed by treatment with NaOH. CMBC removed more Pb2+ than non-modified biochar suggesting that modification with chitosan generates amine groups on the biochar surface which enhance Pb2+ adsorption. Chapter III describes the fast nitrate and fluoride adsorption and magnetic separation from water on iron oxide particles dispersed on Douglas Fir biochar. Nitrate and fluoride adsorption occurred by electrostatic attraction over the wide 2 to 10 pH range. In the chapter IV, aniline and nitrobenzene removal from water was studied using magnetized and nonmagnetized Douglas Fir biochar. The adsorption of aniline and nitrobenzene occurred mainly through pi-pi electron interactions over the wide 2 to 12 pH range and H-bonding. The surface morphology, chemistry, and composition of the modified biochars were examined by SEM, SEM-EDX, TEM, PZC, XPS, XRD, FTIR, TGA, DSC, elemental analysis, and surface area measurements.

The first part of the thesis includes examining inorganic/organic hybird layered solids, also termed “clay mimics.” Transmission and scanning electron microscopy techniques were used to characterize particles before and after intercalation of pyridine based groups. The particle sizes, shape, and surface morphology were studied for a control and five intercalated species, and evidence for change in particle size and shape was found. The second part of the thesis involves a study in the area of inorganic-organic perovskite networks. Variations in the nature of the cationic organic portion as well as the divalent metal halides have been used to try to better predict the type of network formed. In the work reported here, metal halide and ortho-substituted anilines are combined to relate metal halide network dimensionalities to the steric demands of the ortho- substituents on aniline species. The study involved divalent d10 metal halides, and the halides used were: chloride, iodide, and bromide. The anilines used had varied substituents ortho- to the ammonium group, in order to encompass a wide range of substituents. The goal of the study was to determine if the nature of the ortho-substituent caused consistent effects on the resulting crystal structure. Crystals were grown using slow evaporation techniques and viable crystals were characterized using single crystal X-ray diffraction.

No description available.

Cette thèse présente une étude complète de la structure et de la dynamique moléculaire dans une famille de composés conducteurs de la polyaniline plastdopée. Différentes techniques expérimentales ont été combinées dans cette étude comme la diffraction aux grands angles et la diffusion aux petits angles des rayons X (WAXS et SAXS), la diffusion incohérente quasi-élastique des neutrons et les simulations numériques de dynamique moléculaire basées sur les méthodes à champ de force.<br />Cette combinaison a permis de proposer un modèle de structure stable de type lamellaire pour ces composés présentant des fluctuations statistiques de densité électronique le long de l'axe d'empilement des couches moléculaires. De plus, il a été possible d'analyser en détails l'anisotropie structurale et l'évolution structurale des films sous étirement à la lumière de ce modèle.<br />Enfin, une seconde moitié de la thèse est consacrée à l'analyse des données de dynamique obtenues avec les mesures de diffusion quasi-élastique des neutrons. Il a été possible de montrer que l'essentiel de la dynamique dans la fenêtre de temps 10-13-10-9 s provient du mouvement des protons portés par les queues flexibles des dopants. Cette dynamique est très distribuée en temps et aussi dans l'espace tant le long de chaque plast-dopant que parmi les plast-dopants entre eux. Les résultats de simulation numérique sont en accord remarquable avec ces mesures expérimentales. Les trajectoires des atomes calculées dans ces simulations ont permis de recalculer toutes les fonctions de diffusion mesurées par ailleurs expérimentalement. Les simulations ont non seulement confirmé les hypothèses sur lesqueslles avait été bâti un modèle analytique pour la dynamique mais de plus ont révélé des précisions sur la façon dont la dynamique est distribuée entre les contre-ions.

Cancer is the second leading cause of death after cardiovascular diseases in the world. Many of the chemical carcinogens need metabolic activation that catalyzed by cytochrome P450 and Phase II enzymes in order to exert their genotoxic and carcinogenic effects. Hence one possible mechanism is that phenolic compounds may alter anticarcinogenic effects is through an interaction with these enzymes either by the inhibition or activation of certain forms, leading to a reduced production of the ultimate carcinogen. Therefore anti-carcinogen activity of tannic acid, a hydrolyzable plant polyphenol, has a crucial importance to prevent conversion of pro-carcinogens to their carcinogenic form. Tannic acid is produced from secondary metabolism of plants and is found in edible vegetables, fruits and nuts, especially tea, cocoa, coffee and wine. In the present work, modulation of rabbit liver and kidney microsomal P450 dependent aniline 4-hydroxylase, N-nitrosodimethylamine N-demethylase and p-nitrophenol hydroxylase activities and cytosolic phase II enzymes / glutathione S-transferase (GST), NAD(P)H:quinone oxidoreductase:1 (NQO1) were studied in the presence of tannic acid at concentrations ranging from 0.5 &micro / M to 150 &micro / M in the reaction medium. The results obtained in this study were shown that tannic acid significantly inhibited the activities of p-nitrophenol hydroxylase, aniline 4-hydroxylase, NDMA N-demethylase, glutathione S-transferase, NAD(P)H:quinine oxidoreductase 1. Tannic acid was found to be the most potent inhibitor of cytosolic glutathione S-transferase with IC50 of 0.33 &micro / M and the least potent inhibitor of microsomal aniline 4-hydroxylase.with IC50 of 60.26 &micro / M. Effect of tannic acid on enzyme activities was further studied for both mode and type of inhibition. For this purpose various concentrations of the substrate were examined at various tannic acid concentrations. Lineweaver-Burk and Dixon plots were then generated from the resulting data sets. The Km value and inhibition constants (KI) were determined from double reciprocal and Dixon plot of the enzyme activity versus substrate and inhibitor concentration, respectively. Tannic acid was shown to be a noncompetitive inhibitor for liver cytosolic GST, NQO1 and microsomal aniline 4- hydroxylase enzymes with KI of 0.3 &micro / M, 41 &micro / M and 54.7 &micro / M, respectively. On the other hand, in kidney tissues, tannic acid was an uncompetitive inhibitor of cytosolic GST, while it was noncompetitive inhibitor for cytosolic NQO1 with a KI of 12.6 &micro / M. These results indicate that tannic acid may modulate cytochrome P450 dependent and Phase II enzymes and influence the metabolic activation of xenobiotics mediated by these enzymes.

ABSTRACT EFFECT OF PREPARATION AND OPERATION PARAMETERS ON PERFORMANCE OF POLYETHERSULFONE BASED MIXED MATRIX GAS SEPARATION MEMBRANES Karatay, Elif M.Sc., Department of Chemical Engineering Supervisor : Prof. Dr. Levent Yilmaz Co-supervisor : Assoc. Prof. Dr. Halil Kalip&ccedil / ilar August 2009, 126 pages Membrane processes have been considered as promising alternatives to other competing technologies in gas separation industry. Developing new membrane morphologies are required to improve the gas permeation properties of the membranes. Mixed matrix membranes composing of polymer matrices and distributed inorganic/organic particles are among the promising, developing membrane materials. In this study, the effect of low molecular weight additive (LMWA) type and concentration on the gas separation performance of neat polyethersulfone (PES) membranes and zeolite SAPO-34 containing PES based mixed matrix membranes was investigated. Membranes were prepared by solvent evaporation method and annealed above the glass transition temperature (Tg) of PES in order to remove the residual solvent and erase the thermal history. They were characterized by single gas permeability measurements of H2, CO2, and CH4 as well as scanning electron microscopy (SEM), thermal gravimetric analysis (TGA), and differential scanning calorimetry (DSC). Various LMWAs were added to the neat PES membrane at a concentration of 4 wt %. Regardless of the type, all of the LMWAs had an anti-plasticization effect on PES gas permeation properties. 2-Hydroxy 5-Methyl Aniline, HMA, was selected among the other LMWAs for parametric study on the concentration effect of this additive. The incorporation of SAPO-34 to PES membranes increased the permeabilities of all gases with a slight loss in selectivities. However, the addition of HMA to PES/SAPO-34 membranes increased the ideal selectivities well above the ideal selectivities of PES/HMA membranes, while keeping the permeabilities of all the gases above the permeabilities of both pure PES and PES/HMA membranes.

Thesis (Ph. D.)--University of Washington, 2003. / Vita. Includes bibliographical references (leaves 164-177).

Au cours de ces travaux de thèse, une voie de synthèse de différentes cyclopropylamines a été développée. Leur fonctionnalisation a ensuite été mise en œuvre à l'aide de réactions de métallation ou de couplages croisés catalysés au palladium. Les cyclopropylamines ainsi fonctionnalisées furent alors soumises à des conditions de cyclisation dans le but d'obtenir tout ou partie d'une structure 14-azastéroïde. Si notre modèle, dont la synthèse s'est construite autour d'une aniline, nous a permis d'obtenir la structure des cycles B, C et D d'un 14-azastéroïde, nous n'avons pas été en mesure d'obtenir la structure dans sa totalité en partant d'une naphtylamine. Nous avons cependant dans ce cas obtenu un arrangement original pentacyclique comportant un motif cyclobutane. Nous avons enfin réalisés des travaux sur des réactions de type condensation, principalement entre divers dérivés d'aniline et le pyruvate d'éthyle. Lors des résultats préliminaires, nous avons cette fois encore majoritairement obtenu des structures comportant un motif cyclobutane et non celles se rapprochant des azastéroïdes.

The first chapter of this thesis describes the motivation behind using room temperature ionic liquids (RTILs) in gas sensor research and reviews current applications of RTILs in various sensors. The second chapter describes electrochemical polymerization of aniline in room temperature 1-butyl-3-methylimmidazolium ionic liquids without addition of any acid. It is shown that the polymerization of aniline in BMI(BF4) does require small but controlled amounts of water whereas the polymerization in BMI(PF6) and in BMI(TF2N) does not require any water addition. The third chapter describes the construction of reference electrodes for RTIL applications that have a known and reproducible potential versus the ferrocene/ ferrocenium couple. They are based on reference electrodes of the first kind, Ag/Ag+ couple type, or of the second kind, based on Ag/AgCl in M+Cl-. The stability, reproducibility, and temperature behavior of the two reference systems have been characterized. The fourth chapter describes the electrochemical preparation and spectral analysis of gold clusters by adding gold atoms one-by-one through polyaniline s ability to form a strong complex with chloroaurate at the protonated imine sites. Our results confirm that both the amount and the size of gold clusters affects the properties of the composite material. The fifth chapter describes the development and characterization of a CHEMFET sensing layer based on a composite of CSA-doped polyaniline (PANI), and the room temperature ionic liquid BMI(TF2N) for the sensing of ammonia gas. The work function responses of the cast films with and without IL are analyzed by step-wise changes of ammonia gas concentration from 0.5 to 694 ppm in air as a function of the mole fraction of IL to PANI. The PANI CSA/BMI(TF2N) layers shows enhanced sensitivities, lower detection limit and shorter response times. The final chapter describes the preparation and characterization of field-effect transistors with mixed ionic-electronic conductors that have been created by varying the ratio of room temperature ionic liquid and emeraldine salt of polyaniline. Transistor with high electronic conductivity (32mol% ES-PANI) and Au gate contact exhibited theoretical behavior of an IGFET; whereas, the purely ionic gate behaved irreproducibly, indicating that a capacitive divider has been formed in the gate.