O presente trabalho procura dar continuidade a uma das linhas de pesquisa desenvolvida pelo Grupo de Química Analítica do Instituto de Química da Universidade de são Paulo: o estudo da formação de complexos. O sistema Hg(II) / S2O2-3 foi analisado potenciometricamente, com a finalidade de identificar o número de complexos formados, assim como estimar as constantes de estabilidade envolvidas no fenônemo de complexação. Tal equilíbrio foi levado a termo a 25,0 ± 0,1°C, e força iônica 2,00M, sendo detectados quatro espécies complexas. O modelo matemático que melhor se ajustou aos dados experimentais fornecidos pelo sistema, conta com os seguintes valores para as constantes globais de formação: β1 1 = x 1024 M-1 (valor atribuído) β2 = (8,0 ± 2,8) x 1027 M-2 β3 = (1,71 ± 0,03) x 1030 M-3 β4 = (3,07 ± 0,77) x 1030 M-4. Na região de baixa concentração analítica de ligante, 5mM, o acesso experimental foi limitado pela precipitação de sulfeto mercúrico sendo impossível obter informaçôes sobre a primeira espécie. O comportamento do mercúrio no sistema Hg(II) / S2O2-3 foi estudado de uma forma mais abrangente, sendo estendido ao meio não complexante, onde o equilíbrio de dismutação do cátion mercuroso governa. Nas mesmas condições de temperatura e força iônica anteriores, foram obtidos alguns parâmetros desse equilibrio, a saber: - potenciais formais de eletrodo: Eo\'Hg(I) / Hg(O) = ( 0,456 ± 0,014 ) V Eo\'Hg(II) / Hg(O) = ( 0,559 ± 0,0016) V Eo\'Hg(III) / Hg(I) = ( 0, 6625 ± 0,0023 ) V - constante do equilibrio heterogêneo: Qp (potenciométrica) = (3 ± 1) x 103 Adicionalmente, foram realizados estudos eletrogravimétricos sobre o mecanismo de oxidação coulométrica do mercúrio metálico, em diversos eletrólitos suporte, merecendo destaque a estabilização do Hg(I) por cloreto, e do Hg (II) por tiossulfato, mostrando que a transferência eletrônica é um processo por etapas. Complementando o estudo do sistema, a potencialidade análitica do tiossulfato na determinação dos cátions do mercúrio foi confirmada em titulações potenciométricas. / The present work belongs to one of the topics developed by the Analytical Chemistry Group in the Chemistry Institute of the são Paulo University: the study of complex formation equilibrium. The Hg(II)/S2O2-3 system was potentiometrically analysed with the purpose of identifying the number of formed complexes as well as computing their stability constants. Such equilibria study was performed at a 25.0 ± 0.1ºC temperature and 2.00 M ionic strengh, mantained with NaClO4. Four stepwise complexes have been detected by a calculus procedure based on non-linear regression. The best formation constants set is: β1 1 = x 1024 M-1 (arbitrary value) β 2 = (8,0 ± 2,8) x 1027 M-2 β3 = (1,71 ± 0,03) x 1030 M-3 β4 = (3,07 ± 0,77) x 1030 M-3. At lower ligand concentration, nearly 5mM, the experimental access was limited by the mercuric sulphide precipitation, being impossible to achieve data on the first specie. The mercury performance in the Hg(II)/S2O2-3 system was more widely studied with concern to the non-complexing media, where the disrnutation of mercurous cation leads. With the same previous temperature and ionic stengh conditions, some equilibria parameters have been determined: - electrode potentials: Eo\'Hg(I) / Hg(O) = ( 0,456 ± 0,014 ) V Eo\'Hg(II) / Hg(O) = ( 0,559 ± 0,0016) V Eo\'Hg(III) / Hg(I) = ( 0, 6625 ± 0,0023) V - heterogeneous equilibria constant: Qp = (3 ± 1) x 103. Electrogravimetric studies about the coulometric oxidation mecanism of metallic mercury have also been executed. The oxidation was carried out at several suporting electrolites, regarding the Hg(II) stabilization by the tiossulphate anion, and the Hg(I) by chloride, showing that the electrochemical transfer occurs in a step by step process. In addition to system study, the analytical potentiality of the tiossulphate on the determination of mercury cationic species was confirmed by potentiometric titulations.

Neste trabalho foi avaliado a seletividade de reações biocatalisadas por fungos basidiomicetos frente a compostos bifuncionalizados com os grupos cetona e seleneto (1-2) ou cetona e sulfeto (3-4). Os compostos 1-4 foram sintetizados de acordo com metodologias descritas na literatura. Na síntese dos padrões racêmicos dos β-hidróxi-selenetos 1a-2a e β-hidróxi-sulfetos 3a-4a observou-se que a redução química utilizando NaBH4 levou a formação preferencial dos estereoisômeros cis-(1a-4a). Enquanto que a redução promovida na utilização dos fungos basidiomicetos levou a formação preferencial do estereoisômero trans-(1a-4a). Desta forma duas metodologias complementares para a preparação de β-hidróxi-selenetos e β-hidróxi-sulfetos foram estabelecidas. Cinco linhagens destes fungos (Irpex lacteus CCB 196, Trametes rigida CCB 285, Pycnoporus sanguineus CCB 501, Trametes byssogenum CCB 203, Trametes versicolor CCB 202 ) foram testadas visando à obtenção de β-hidróxi-selenetos (1a-2a) e β-hidróxi-sulfetos (3a-4a) na forma enantiomericamente pura ou enriquecida. Um estudo qualitativo indicou que o fungo Trametes rigida CCB 285 apresentou alta seletividade frente aos compostos utilizados levando aos produtos cis-(1a-4a) e trans-(1a-4a) com elevados valores de excessos enantioméricos (e.e. 99 %). Posteriormente, um estudo quantitativo permitiu o isolamento dos produtos, a determinação dos rendimentos isolados e também a configuração absoluta para os compostos isolados. Na segunda parte deste trabalho avaliou-se a aplicação de fungos Aspegillus terreus em reações de desmetilação/desalquilação de aminas terciárias. Os resultados obtidos indicam que os estes fungos apresentam grande potencial para reações de desmetilação de aminas terciárias aromáticas, sendo que as reações conduzidas em meio neutro (pH = 7) levaram aos produtos desmetilados com bons valores de conversão. No entanto, não foram observadas reações de desalquilação com grupos etila nas condições utilizadas. / In this work was considered the selectivity of reactions biocatalysted by basidiomycetes fungi with bifuncionalized compounds with ketone and selenide groups (1-2) or ketone and thio groups (3-4). The compounds 1-4 were prepared in according with methodologies from literature. During the synthesis of standard racemic β-hydroxyselenides 1a-4a and β-hydroxysulfides 3a-4a we noticed that chemical reduction using NaBH4 led to the preferential formation of the cis-(1a-4a) isomers. On the other hand, the bioreduction promoted by basidiomycetes fungi led to the preferential formation of trans-(1a-4a) isomers. Therefore, two complementary methodologies for preparation of β-hydroxyselenides and β-hydroxysulfides were established. Five strains of basidiomycetes fungi (Irpex lacteus CCB 196, Trametes rigida CCB 285, Pycnoporus sanguineus CCB 501, Trametes byssogenum CCB 203, Trametes versicolor CCB 202) were examined to aim at the preparation of β-hydroxyselenides and β-hydroxysulfides on the enantiomerically pure form. A qualitative study indicated that cells of T. rigida CCB 285 showed high selectivity led to the products cis-(1a-4a) and trans-(1a-4a) in high enantiomeric excess (ca 99 %). After that, a quantitative study allowed us to determine the isolated yields and the absolute configuration for the compounds cis-(1a-4a) and trans-(1a-4a). In the second part of this work was considered the application of Aspergillus terreus fungi in demethylation/dealkylation reactions by tertiary amines. The results indicated that those fungi showed a big potencial for demethylation reaction of aromatic tertiary amines. The reaction done on the pH = 7 led to the demethylated products with good values of conversion. Dealkylation reactions were not observed.

Abstract The results of the comparison of various dissolution methods for sulphur showed, that HNO3 together with H2O2 gave more complete decomposition of organic components than HNO3 alone. The acid procedure with a mixture of HNO3+H2O2 slightly underestimated the S concentrations of plant material. The losses of sulphur were the highest in the dry ashing digestion procedure (HF(DAC)). The Leco combustion technique with infrared (IR) detection gave good precision and accuracy for sulphur. For the determination of heavy metals in plant materials, both the HNO3 and HNO3+H2O2 procedures were especially effective for determining Cr. However, the HNO3+HClO4 procedure gave lower results, and HF and HF(DAC) procedures greater values for Cr. Sulphur accumulation in pine needles around the pulp and paper mills was clearly higher than other points in the Kemi area. For example, within a radius of about 1-1.5 km around the mills of Oy Metsä-Botnia Ab Kemi Mills, the sulphur concentrations for (C) and (C+1) needles were 28 % and 26 % higher than those in the corresponding background samples collected in Kuivaniemi at a distance about 25 km from Kemi. Pine needles do not appeared to be appropriate a method for monitoring the accumulation of Fe, Zn, V and Pb emitted from pulp and paper mills. However, the Ca concentrations in (C+1) needles in the vicinity of the Oy Metsä-Botnia Ab Kemi Mills was 48 % higher than the average Ca concentration calculated from all (C+1) needles; thus it is likely that part of the Ca in the needles is derived from the mills. The regional distribution pattern of Cr and Ni in mosses in the Kemi-Tornio area in 2000 showed clearly that the most polluted area (Cr > 200 μg/g and Ni > 20 μg/g) appeared to lie within a few kilometres of the ferrochrome and stainless steel works of AvestaPolarit Stainless Oy. Within this area, the Cr concentrations in mosses were 4-13 times higher than those outside the urban area of Tornio. The area most polluted by the opencast chromium mining complex (Cr > 200 μg/g and Ni < 20 μg/g) appeared to be in the immediate vicinity of complex. All the 95th percentile values for TSP (total suspended particles) in the mine area of AvestaPolarit Chrome Oy Kemi Mine were below the current Finnish air quality limit value of 300 μg/m3. However, the 98th percentile value exceeded the Finnish air quality guideline value of 120 μg/m3 at one monitoring site. According to leaching studies, the sum of calculated annual airborne pollution impact of water-soluble fraction (H2O) and environmentally mobile (CH3COONH4) fraction from the AvestaPolarit Chrome Oy Kemi Mine was Cr 1.2 kg, Fe 29 kg, Cu 63 kg, Ni 2.5 kg and Cd < 100 mg. According to the homogeneity studies of heavy metal deposition on TSP filters, Cr, Ni, Cu and Fe were non-uniformly distributed over the glass fibre filters. The rsd values varied between 5.4-33.9 % for Cr, between 7.5-35.0 % for Ni, between 3.6-25.9 % for Cu, and between 6.6-19.9 % for Fe.

En agriculture, les ravages causés par les champignons pathogènes sont les plus répandus et les plus dommageables. Au cours du développement parasite, ils présentent un besoin en méthionine et cystéine. Notre étude vise à mieux comprendre le rôle clé de la méthionine dans la physiologie du champignon phytopathogène Magnaporthe grisea. Nous sous sommes focalisés sur deux mutants de délétion obtenus par remplacement de gène : le mutant du gène codant pour la méthionine synthase (mutant ΔMS) et celui du facteur de transcription MgMetR (mutant ΔMgMetR). Une étude globale a été entreprise pour chacun des mutants en utilisant les techniques de transcriptome et de métabolome. Les signatures métaboliques des mutants ont été déterminées par HPLC. Le mutant ΔMS est caractérisé par une accumulation d’homocystéine et de SAM et le mutant ΔMgMetR présente une réduction drastique de son taux de glutathion. L’analyse en transcriptome du mutant ΔMS montre un nombre important de gènes différentiellement exprimés. Plusieurs voies métaboliques se sont vues affectées dans le mutant ΔMS : le métabolisme des folates, la biosynthèse des acides aminés et l’homéostasie du fer ont fait l’objet d’une étude particulière. Les premières analyses bioinformatiques du transcriptome du mutant ΔMgMetR ont confirmé le rôle de MgMetR dans le contrôle de l’expression des gènes de la voie d’assimilation du sulfate. L’ensemble de ces résultats a permis de mettre en évidence de nouvelles connections métaboliques et ainsi, facilite la compréhension du métabolisme du champignon phytopathogène M. grisea afin de trouver de nouvelles voies d’étude pour la protection des cultures. / Filamentous fungi cause devastating diseases in agricultural crops. Recent studies highlighted a need for methionine and cysteine during the infectious process. Our goal is to understand the role of methionine biosynthesis in the plant pathogenic model Magnaporthe grisea. To this end, we focused our study on two null mutants for the genes encoding methionine synthase which catalyzes the last step for methionine biosynthesis (ΔMS), and the sulphur regulator MgMetR which controls sulphate assimilation pathway (ΔMgMetR). A global analysis was carried out for each mutant by using transcriptomic and targeted metabolomic approaches. Metabolic signatures were determined by HPLC. ΔMS mutant was characterized by an increase in homocysteine and S-adenosylmethionine levels whereas ΔMgMetR mutant displayed a drastic reduction in glutathione content. Microarray analyses of ΔMS mutant highlighted an important molecular perturbation since 507 to 1565 genes were differentially expressed in ΔMS mutant compared to the wild type strain depending on our experimental conditions (from starvation to excess of methionine). Our analyses focused on different metabolic pathways: folate metabolism, amino acid biosynthesis and iron homeostasis which were subject to molecular and biochemical validations. Microarray analyses of ΔMgMetR mutant confirmed the transcriptional control of the expression of the genes involved in sulphate acquisition and assimilation. The set of results obtained during this work gets insight into new metabolic interplays between methionine biosynthesis and M. grisea general metabolism and reveals new research areas for antifungal molecules with the aim of crop protection.

Oceans are powered by active, metabolically diverse microorganisms, which are important in regulating biogeochemical cycles on Earth. Most of the ocean surface is often limited by nutrients, influencing bacterial growth and activities. Bacterial adaptation to fluctuating environmental conditions involves extensive reprogramming, and redirection of bacterial metabolism and physiology. In this thesis, I investigated the molecular mechanisms of bacterial adaptation strategies to sustain their growth and survival, focusing on the regulation of gene and protein expression in heterotrophic marine bacteria. Comparative proteomics analyses of the growth and non-growth conditions, uncovered central adaptations that marine bacteria employ to allow them to change their metabolism to support exponential growth in response to nutrients and to readjust to stationary phase under nutrient limitation. Our results highlight that during nutrient rich conditions three distinct bacteria lineages have great similarities in their proteome. On the other hand, we observed pronounced differences in behavior between taxa during stationary phase. Analyses of the proteorhodopsin containing bacterium Vibrio sp. AND4 during starvation showed that significantly improved survival in the light compared to darkness. Notably, proteins involved in promoting cell vitality and survival had higher relative abundance under light. In contrast, cells in the dark need to degrade their endogenous resources to support their basic cellular demands under starvation. Thus, light strongly influences how PR-containing bacteria organize their molecular composition in response to starvation. Study of alternative energy generation metabolisms in the Alphaproteobacteria Phaeobacter sp. MED193 showed that the addition of thiosulfate enhanced the bacterial growth yields. Concomitantly, inorganic sulfur oxidation gene expression increased with thiosulfate compared to controls. Moreover, thiosulfate stimulated protein synthesis and anaplerotic CO2 fixation. These findings imply that this bacterium could use their lithotrophic potential to gain additional energy from sulfur oxidation for both improving their growth and survival. This thesis concludes that analyses in model organisms under defined growth conditions gives invaluable knowledge about the regulatory networks and physiological strategies that ensure the growth and survival of heterotrophic bacteria. This is critically important for interpreting bacterial responses to dynamic environmental changes. Moreover, these analyses are crucial for understanding genetic and proteomic responses in microbial communities or uncultivated organisms in terms of defining ecological niches of planktonic bacteria

This thesis is focused in calculation and designing of fluid bed boiler for burning coal and wood biomass in the form of wood chips. The uniqueness of fluidized bed boiler is circulating fluidized layer and cyclone ash separator from flue gases beyond the combustion chamber.Work was divided into several parts due to different parameters of the fuel.. Stoichiometry calculations, emissions calculations, enthalpy of combustion and flue gas desulphurization calculations are performed in various parts.Further, calculating of the losses of boiler and its efficiency comparing to the calculation and design of each heat transfer surfaces was also solved so that resulting size and quantity meet the required specifications.Drawn set of this designed boiler based on calculations is included in the annex to this paper.

This master’s thesis deals with the influence of different carbon materials on the properties of Li-S accumulators. The theoretical part of the thesis describes primary and secondary electrochemical sources with a focus on medical applications. The second chapter deals individually with a lithium article. The main part of the thesis is the practical production of electrodes for Li-S accumulators using different types of carbon materials. The effects of these materials on the properties of accumulators are investigated to determine the most appropriate in terms of capacity and stability.

This thesis is focused in calculation and designing of fluid bed boiler for burning coal and wood biomass in the form of wood chips. The uniqueness of fluidized bed boiler is circulating fluidized layer and cyclone ash separator from flue gases beyond the combustion chamber.Work was divided into several parts due to different parameters of the fuel.. Stoichiometry calculations, emissions calculations, enthalpy of combustion and flue gas desulphurization calculations are performed in various parts.Further, calculating of the losses of boiler and its efficiency comparing to the calculation and design of each heat transfer surfaces was also solved so that resulting size and quantity meet the required specifications.Drawn set of this designed boiler based on calculations is included in the annex to this paper.

Goal of this diploma thesis was to determine influence of graphitizing inoculation and chemical composition on structure and mechanical properties of gray iron. In terms of chemical composition, sulphur content was to be observed. Hardness and tensile strength were measured. Metallographic samples were analyzed by image analysis software.

Aim of this thesis is to design a technology of a flue gas desulphurization of fluidized bed boiler. Currently, the state of technology is not able to provide flue gas desulphurisation to required level. For this reason it is necessary to build additional device for the desulphurisation. Theoretical part of the thesis deals with the emission limits of sulphur dioxide, available methods of desulphurization and sorbents suitable for the desulfurization. In practical part conditioned dry sorption method is chosen for the specified source, technological and structural design for suggested desulphurization technology including design of all device is proposed. The thesis also includes a technology design and a 3D model.