This work deals with the study of organic matter in the South Moravian lignite using the available physico-chemical methods and the results obtained are eventually considered for non-energy applications of lignite. Lignite organic matter was studied by degradation methods, which included CuO oxidation, thermochemolysis with TMAH and DFRC method. Special attention was paid to the lignite oxidation with hydrogen peroxide, which was carried out under different reaction conditions (time and temperature). Thermal degradation was performed in an inert atmosphere in order to observation of chemical change of lignite (including lignite after extraction with chloroform, demineralised lignite, remineralised lignete) during pyrolysis by means of various methods, especially TG-FTIR for analysis of gaseous products and FTIR for analysis the residual lignite after pyrolysis. Further, water-soluble fractions from lignite were characterized, particularly in terms of the content of organic substances.

In cystic fibrosis (CF), pancreatic insufficiency and a diminished bile acid pool cause malabsorption of important nutrients and dietary components leading to deficiency, poor nutritional status, and oxidative stress. Of particular significance is the malabsorption of fat-soluble nutrients and antioxidants, which are important for normal immune and neurologic function. Patients with CF often are deficient in these compounds despite supplementation with the current standard of care therapy. The objective was to compare the pharmacokinetic profile of this water-soluble vitamin E formulation (Aqua-E) with an oil-based softgel formulation in a malabsorbing patient population. Patients with CF who had documented malabsorption were recruited for participation in this pharmacokinetic study. Patients who met inclusion and exclusion criteria discontinued vitamin E supplementation, except for that in a multivitamin, for 7 to 21 days before the day of dosing. Patients were randomized to a single dose of 20 ml of Aqua-E or three oil-based softgels, which contained equivalent amounts of tocopherols. Blood was drawn from patients at time 0, 2, 4, 8, 24, 48, and 168 hr and analyzed for tocopherols. Eight patients were enrolled in the study and randomized to Aqua-E or softgels. The primary outcome, the absorption of γ-tocopherol in Aqua-E (AUC=115 μg/ml*hr), was significantly greater than that of oil-based softgels (AUC=25.3 μg/ml*hr; P=0.013). Total-tocopherols (α+γ +δ) in Aqua-E (AUC=294 μg/ml*hr) showed a strong trend toward increased absorption compared with that of oil-based softgels (AUC=117 μg/ml*hr; P=0.09). In conclusion, this novel, water-soluble formulation showed a marked and statistically significant increase in absorption of γ-tocopherol in malabsorbing patients with CF compared with an oil-based formulation.

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<p>This work focused on grafting water-soluble polymers with well-controlled properties such as tuneable polymer chain length and high graft density to improve the biocompatibility of polymer surfaces via surface-initiated atom transfer radical polymerization (s-ATRP); and on gaining improved fundamental understanding of the mechanisms and factors (e.g., graft chain length and surface density of monomer units) in protein resistance of the water-soluble grafts.</p><p>Protein-resistant polyurethane (PU) surfaces were prepared by grafting watersoluble polymers including poly(oligo(ethylene glycol) methacrylate) (poly(OEGMA)) and poly(l-methacryloyloxyethyl phosphorylcholine) (poly(MPC)) via s-ATRP. A typical three-step procedure was used in the ATRP grafting. First, the substrate surface was treated in an oxygen plasma and reactive sites (-OH and -OOH) were formed upon exposure to air. Second, the substrate surface was immersed in 2-bromoisobutyryl bromide (BffiB)-toluene solution to form a layer of ATRP initiator. Finally, target polymer was grafted from the initiator-immobilized surface by s-ATRP with Cu(I)Br/2bpy complex as catalyst. The graft chain length was adjusted by varying the molar ratio of monomer to sacrificial initiator in solution. The modified PU surfaces were characterized by water contact angle, X-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM).</p><p>Protein adsorption experiments were carried out to evaluate the protein resistance of the surfaces. Adsorption from single and binary protein solutions as well as from plasma decreased significantly after poly(OEGMA) grafting, and decreased with increasing poly(OEGMA) main chain length. Fibrinogen (Fg) adsorption on the most resistant surfaces (chain length 200 units) was in the range of 3-33 ng/cm^2, representing a reduction of more than 96% compared to the control surfaces.</p><p>OEGMA monomers with three different molecular weights (MW 300, 475, 1100 g/mol) were used to achieve different side chain lengths of poly(OEGMA). Fibrinogen (Fg) and lysozyme (Lys) were used as model proteins in adsorption experiments. The effects of side chain length as well as main chain length were then investigated. It was found that adsorption to the poly(OEGMA)-grafted PU (PU/PO) surfaces was protein size dependent. Resistance was greater for the larger protein. For grafts of a given side chain length, the adsorption of both proteins decreased with increasing polymer main chain length. For a given main chain length, the adsorption of Fg, the larger protein, was independent of side chain length. Surprisingly, however, Lys (the smaller protein) adsorption increased with increasing side chain length. A reasonable explanation is that graft main chain density decreased as monomer size and footprint on the surface increased. Protein size-based discrimination suggests that the chain density was lower than required to form layers in the "brush" regime in which protein size is expected to have little effect on protein adsorption.</p><p>In order to achieve high surface densities of ethylene oxide (EO) units, we used a sequential double grafting approach whereby the surface was grafted first with poly(2-hydroxyethyl methacrylate) (HEMA) by s-ATRP. OEGMA grafts were then grown from the hydroxyl groups on HEMA chains by a second ATRP. The effect of EO density on protein-resistant properties was then investigated. Protein adsorption on the sequentiallygrafted poly(HEMA)-poly(OEGMA) surfaces (PU/PH/PO) was not only significantly lower than on the unmodified PU as expected, but also much lower than on the PU/PO surfaces with the same poly(OEGMA) chain length. Moreover, protein adsorption decreased with increasing EO density for these grafts. On the PU/PH/PO surface with a poly(OEGMA) chain length of 100, the adsorption of Ls and Fg were reduced by ~98% and >99%, respectively, compared to the unmodified PU. Binary protein adsorption experiments showed that suppression of protein adsorption on the PU/PH/PO surfaces was essentially independent of protein size. The double-grafted OEG layers resisted both proteins equally.</p><p>The general applicability of this approach which combines oxygen plasma treatment and ATRP grafting was also studied. Various kinds of polymers such as PU, silicone hydrogel, and polydimethylsiloxane (PDMS) were chosen as substrates. Poly(MPC) grafts with different chain lengths were achieved by the three-step ATRPgrafting procedure. It was found that protein adsorption levels on the poly(MPC) grafts were significantly lower than on the respective unmodified surfaces. Protein adsorption decreased with increasing poly(MPC) chain length. Among the surfaces investigated, PU/MPC showed the highest protein resistance for a given chain length.</p> / Thesis / Doctor of Philosophy (PhD)

<p> High molecular weight poly(ethylene oxide) (PEO) is used in conjunction with a cofactor such as phenol formaldehyde resin (PFR) as flocculants for newsprint manufacture. The objectives of the work described in this thesis were to prepare flocculants superior to PEO and to determine the flocculation mechanism. A series of novel comb copolymers consisting of a polyacrylamide backbone with short pendant poly(ethylene glycol) (PEG) chains was prepared and characterized. Additionally, polymerization conversion curves and reactivity ratios were measured. An interesting finding was that the reactivity of the macromonomer in free radical copolymerization decreased with PEG chain length. </p> <p> Flocculation results with both model latex dispersions and commercial wood pulp suspensions showed that copolymer chain length was the most important variable ; molecular weights greater than 3 million were required for good flocculation. On the other hand, the PEG pendant chains could be as short as 9 ether repeat units. Also, only 1 to 2 PEG chains for every 100 acrylamide backbone moieties were required. </p> <p> No published flocculation mechanisms could predict all the behaviors of the PEO or copolymer system. A new mechanism called complex bridging was proposed. According to this mechanism PEO or copolymer chains aggregate in the presence of cofactor to form colloidally dispersed polymer complex which heteroflocculates with the colloidal particles. </p> <p> Given in this work is the first explanation of the requirement for extremely high PEO or copolymer molecular weights for flocculation. It is proposed that polymer chains with molecular weights less than 106 collapse in the presence of PFR to an inactive precipitate before flocculation can occur whereas complexes based on very high molecular weight PEO collapse slowly enough to permit flocculation. </p> <p> Published mechanistic studies are hindered by the fact that PFR has poorly defined structures. It is shown for the first time in this work that welldefined, linear, poly(p-vinyl phenol) (PVPh) is an effective cofactor. </p> / Thesis / Doctor of Philosophy (PhD)

Li-ion batteries have enabled the widespread adoption of portable electronics and are becoming the technology of choice for electric vehicles and grid storage. One of the most promising ways to accommodate this demand is to increase the energy density and cycle life of battery electrode materials. Key strategies promoted in the literature include the use of nickel-rich cathodes as well as high-capacity anodes like silicon and lithium metal. While these materials enable a high energy density, this advantage is often counterbalanced with deficits such as poor stability and high cost. Multicomponent electrodes refer to strategies that try to leverage the relative advantages of different materials to offer an attractive compromise of energy density, cost, and cycle life. This thesis has investigated various aspects of multicomponent electrodes with a special emphasis on silicon-based anodes and high-entropy materials. Silicon (Si) is the second-most abundant element on earth and has one of the highest gravimetric capacities. However, silicon anodes are notorious for their poor cycle stability. Herein, improvements in the stability of silicon-based electrodes are achieved with multicomponent composite strategies involving the use of nanostructured spherical silicon. The nanosilicon is studied in high-fraction (80 wt% Si) and low-fraction (≤20 wt% Si) formulations to investigate both failure mechanisms and practical capacity retention, respectively. Composite strategies in which nanosilicon is encapsulated within a Li₄Ti₅O₁₂ ceramic or MOF-derived carbon matrix are shown to deliver superior capacity retention compared to simple composites of silicon and graphite. Considerable attention is given to the selection of a water-soluble binder and its role in electrochemical stability and electrode cohesion in high-loading silicon electrodes. It is found that unmodified high-molecular-weight sodium carboxymethyl cellulose offers better capacity retention compared to xanthan gum or low-molecular-weight binders. The high-entropy design strategy has created a diverse and largely unexplored set of multicomponent oxides and alloys with great potential as electrode materials. This strategy is applied to the family of layered cathodes, where the synthesis and electrochemical properties of the best-performing Li(NiCoMnTiFe)₁O₂ are reported. Despite the low Ni content, the cathode delivers a high initial capacity with unique overlithiation stability despite being charged to 4.4 V. Throughout the thesis, Operando XRD is used to reveal important insight into the lithiation mechanisms of the multicomponent electrodes including intercalation-based graphite, alloying-based silicon, and a novel organic azaacene.

京都大学 / 新制・課程博士 / 博士(農学) / 甲第25018号 / 農博第2578号 / 新制||農||1103(附属図書館) / 京都大学大学院農学研究科森林科学専攻 / (主査)教授 梅村 研二, 教授 矢野 浩之, 教授 村田 功二 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM

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