The study was inspired by the need to assess long-term metal retention in municipal solid waste (MSW) landfills. The long-term processes in landfills are poorly known due to the relatively short time that such landfills have been in existence. Natural analogues where similar metal binding processes could be expected were therefore sought for. The work described in this thesis aims to elucidate the long-term transport and attenuation processes involved in the retention of heavy metals in a peat bog, through field studies and modelling. The Oostriku peat bog (central Estonia) has been exposed to metal-rich groundwater discharge over a long period of time and was found to have accumulated high concentrations of Fe, other heavy metals (e.g. Pb, Cu, Zn, Mn), and As. It was characterised in detail with respect to metal depth distribution and main metal binding mechanisms (using an optimised Tessier extraction scheme). The oxidation of metal sulphides in the surrounding carbonate bedrock was proposed to be a possible long-term source of heavy metals in the water emerging in a spring at the peat site. The water in the spring and peat pore-water was sampled and analysed. The dissolution sequence of the sulphide minerals and evolution of the water composition along a flowpath in the carbonate rock were modelled. Resulting aqueous phase concentration of major and minor elements are discussed in relation to governing geochemical processes. The simulated water composition was compared with that observed. Retention of metals transported with water through the peat was assessed through modelling equilibrium sorption on solid organic matter and amorphous ferric oxyhydroxide by using a simplified quantitative modelling approach and independently obtained data. Dynamic evolution of metal sorption fronts along a peat profile over time was modelled to test metal-metal competition effects. A possible formation of ferric oxyhydroxide in the peat bog was also assessed with the model. / QC 20101001

S’ha estudiat la formació de sulfur d’hidrogen (H2S) i altres compostos de sofre volàtils lleugers com els mercaptans i disulfurs per part dels llevats durant la fermentació vínica. Es proposen mètodes per mesurar i evitar el problema de l’olor desagradable del H2S i els seus derivats, des de la vinya, el most, els llevats i el vi, i respectar les aromes pròpies de cada varietat. S’han analitzat diferents factors de la producció dels compostos de sofre, la descripció dels defectes associats, la formació dels sulfurs: anàlisi, identificació i quantificació dels sulfurs en vins, s’han identificat compostos com l’etil mercaptà, sulfur de dimetil i en menor quantitat el sulfur de dietil i el sulfur de metil. S’ha estudiat el moment de la formació en mostos model, i s’ha vist una o dues fases durant la fermentació on la producció de sulfur és alta. S’han estudiat les aromes típiques de varietats locals mitjançant l’anàlisi sensorial descriptiva. En un estudi de soques de llevat, s’ha observat que la majoria (60%) produeixen alguna quantitat de sulfurs durant la fermentació i que l’elecció de la soca és un factor important. S’han provat tres tipus de reg en vinya i s’ha vist que influeix en els estils dels vins i en els compostos nitrogenats dels mostos resultants. En vinya per la prevenció de l’oïdi es van fer tractaments alternatius sense sofre, per tal d’evitar la formació de sulfurs. Per a identificar el component genètic de la producció de H2S s’han comparat els transcriptomes de dues soques amb propietats enològiquessimilars, però diferent producció de H2S: UCD 522 (alta producció) i P29 (baixa producció). Les mostres es van extreure durant fermentacions en el moment de màxima producció de H2S. Degut a què no eren soques de laboratori es van fer tres tipus d’estudi del perfil de transcripció de les dues soques de llevat: un array basat en el cADN, un array basat en oligonucleòtids i un anàlisi per qRTPCR d’una selecció de transcripts. Els resultats foren similars amb les tres tècniques. Més del 90% dels gens no van mostrar diferències entre les dues soques. En canvi, la majoria dels gens relacionats amb la biosíntesi de la tiamina van tenir una sobreexpressió a la soca amb alta producció de H2S. Per contra, gens relacionats amb el catabolisme dels aminoàcids, una possible font de H2S, no van mostrar diferències d’expressió entre les dues soques. Això suggereix que, en les condicions estudiades, el metabolisme secundari com la biosíntesi de la tiamina i altres compostos amb sofre pot ser clau per explicar la producció de H2S per algunes soques de llevat durant la fermentació. En vins amb defectes de compostos de sofre volàtil s’han tractat amb citrat de coure i s’ha vist que podia ser una alternativa al sulfat de coure que s’ha fet servir tradicionalment.

Macroscopical and microscopical observations on extant and fossil plants have been made. Observations on extant plants led to study the effects of volcanic gases on the cuticle ultrastructure of Pinus halepensis and Erica arborea sampled in the volcanic area of Phlegrean Italy. TEM observations on P. halepensis cuticles fumigated or not by volcanic gases revealed: 1) insignificant thickness variations of the cell wall plus cuticle among current- and first-year-old needles of both fumigated and not fumigated trees; 2) a calcium oxalate accumulation in fumigated leaves; 3) moreover, in respect to the cell surface, fibrils are disposed parallel to the surface of the cuticle. In specimens of E. arborea fumigated or not by volcanic gases, 1) the total thickness of cuticles varies significantly; 2) in plants experiencing chronic fumigation the A2 layer increases its thickness. As for fossil plants, the cuticles of Cretaceous Fossil-Lagertätten of Cusano Mutri and Pietraroja have been studied. In the former: 1) numerous taxa belonging to conifers have been identified; 2) the new species Frenelopsis cusanensis has been described; 3) Montsechia vidalii has been found outside of Spain. Taxonomical studies allowed the description of typical Euro-Sinian fossil plants. Sedimentological and taxonomical studies suggest semi-arid or arid conditions in a subtropical or tropical climate. It is worth noting as for Cusano Mutri locality, evidence of wildfire (fusain) suggests a periodic combination of arid periods, high temperatures and lightning strikes.

The past decade has witnessed dramatic changes in the oil and gas industry with the drilling and production extending into progressively deeper waters and higher operating pressures, therefore making it essential to gain a better understanding of the behaviour of gas hydrate at high pressure conditions. New experimental 3-phase H−LW−V (Hydrate−Liquid Water−Vapour) equilibrium data for nitrogen and H−LW−V (Hydrate−Liquid Water−Vapour) and H−LW−LHC (Hydrate−Liquid Water−Liquid Hydrocarbon) data for ethane and propane simple clathrate hydrates were generated by a reliable fixed-volume, isochoric, step-heating technique. The accuracy and reliability of the experimental measurements are demonstrated by comparing measurements with reliable literature data from different researchers. Additional experimental data up to high pressure (200 MPa when available) for CH4, C2H6, C3H8, i-C4H10, N2, Ar, Kr, Xe, H2S, O2, CO and CO2 clathrates have been gathered from literature. The Valderrama modification of the Patel-Teja (VPT) equation of state combined with non-density-dependent (NDD) mixing rules is used to model the fluid phases with previously reported binary interaction parameters. The hydrate-forming conditions are modelled by the solid solution theory of van der Waals and Platteeuw. Langmuir constants have been calculated by both Kihara potential as well as direct techniques. Model predictions are validated against independent experimental data and a good agreement between predictions and experimental data is observed, supporting the reliability of the developed model.

Research and evaluation of effect of traditional (iron salts) and alternative iron source (ochre) on anaerobic digestion of sludge mixture process have been made in dissertation. Research has been made in two European countries: Lithuania and Sweden. Sludge mixture used for the experiments was from biological phosphorus removal plants; ochre originated from groundwater treatment plants. Case study, laboratory and pilot-scale experiments have been made for the complex evaluation of impact of ochre on sludge digestion process. Standard and specific methodics were used for the evaluation of results. Based on results technology for using of ochre for the improving of the anaerobic digestion process at the treatment plants with biological phosphorus treatment has been proposed. / Disertacijoje nagrinėjamas ir vertinamas tradicinio (geležies druskų) ir alternativaus geležies šaltinio (geležies paplavų) poveikis anaerobinio dumblo mišinio pūdymo procesui. Tyrimai buvo atlikti dviejose Europos Sąjungos šalyse: Lietuvoje ir Švedijoje. Tyrimams dumblo mišinys imtas iš biologinio fosforo šalinimo įrenginių; geležies paplavos – iš požeminio vandens gerinimo įrenginių. Siekiant kompleksiškai įvertinti geležies paplavų įtaką dumblo pūdymo procesui, buvo atlikti natūriniai, laboratoriniai ir pusiau gamybiniai tyrimai. Darbe panaudotos standartinės ir specifinės pūdymo proceso kokybės nustatymo metodikos. Remiantis gautais rezultatais buvo pasiūlyta technologinė geležies paplavų panaudojimo dumblo apdorojimo ūkyje, skirta nuotekų valymo įrenginiams su biologiniu fosforo šalinimu.

Disertacijoje nagrinėjamas ir vertinamas tradicinio (geležies druskų) ir alternativaus geležies šaltinio (geležies paplavų) poveikis anaerobinio dumblo mišinio pūdymo procesui. Tyrimai buvo atlikti dviejose Europos Sąjungos šalyse: Lietuvoje ir Švedijoje. Tyrimams dumblo mišinys imtas iš biologinio fosforo šalinimo įrenginių; geležies paplavos – iš požeminio vandens gerinimo įrenginių. Siekiant kompleksiškai įvertinti geležies paplavų įtaką dumblo pūdymo procesui, buvo atlikti natūriniai, laboratoriniai ir pusiau gamybiniai tyrimai. Darbe panaudotos standartinės ir specifinės pūdymo proceso kokybės nustatymo metodikos. Remiantis gautais rezultatais buvo pasiūlyta technologinė geležies paplavų panaudojimo dumblo apdorojimo ūkyje, skirta nuotekų valymo įrenginiams su biologiniu fosforo šalinimu. / Resarch and evaluation of effect of traditional (iron salts) and alternative iron source (ochre) on anaerobic digestion of sludge mixture process have been made in dissertation. Research have been made in two European countries: Lithuania and Sweden. Sludge mixture used for the experiments was from biological phosphorus removal plants; ochre originated from groundwater treatment plants. Case study, laboratory and pilot-scale experiments have been made for the complex evaluation of impact of ochre on sludge digestion process. Standard and specific methodics were used for the evaluation of results. Based on results technology for using of ochre for the improving of the anaerobic digestion process at the treatment plants with biological phosphorus treatment have been proposed.

The oxidative dissolution of chalcopyrite in ferric media often produces incomplete copper recoveries. The incomplete recoveries have been attributed to inhibition caused by the formation of a metal deficient sulphide and the deposition of elemental sulphur and jarosite. Although these phases have been qualitatively identified on the surface of chalcopyrite, none have been quantitatively identified. The aim of the project was to quantitatively analyse the surface before and after oxidative dissolution, with X-ray photoelectron spectroscopy (XPS), and to use the phases identified as the basis for mechanisms of dissolution and inhibition. / XPS analysis was performed on chalcopyrite massive fractured under anaerobic atmosphere and chalcopyrite massive and concentrate oxidised in 0.1 M ferric sulphate (pH 1.9) and 0.2 M ferric chloride (pH 1.6) at 50, 65 and 80ºC. Quantitative XPS analysis of the chalcopyrite surfaces required the development of programs that accounted for the observed XPS spectra. The output of these programs was used to construct profiles of the chalcopyrite surfaces and the deposited phases. These surface profiles were correlated with copper recoveries determined for chalcopyrite concentrate dissolution under the same conditions. / The surface of chalcopyrite before oxidative dissolution reconstructs to form a `pyritic' disulphide phase. This phase is oxidised in ferric media to form thiosulphate via the incorporation of oxygen atoms from the hydration sphere. The thiosulphate reacts in the oxidising conditions of low pH to form elemental sulphur, sulphite and sulphate. The sulphate complexes with ferric to produce hydronium jarosite. This reaction occurs at the surface during the initial stages of dissolution and in the bulk solution during the latter stages. This precipitation of hydronium jarosite during the latter stages of dissolution corresponds to inhibition of the dissolution reaction. It is therefore concluded hydronium jarosite is responsible for inhibiting the oxidative dissolution of chalcopyrite in ferric media. / The identification of hydronium jarosite as the inhibiting phase is consistent with the industrial practice of removing `excess' iron from the ferric solution before oxidative dissolution. However, additional iron and sulphate are generated at the chalcopyrite surface during oxidative dissolution. These high iron and sulphate concentrations combine with the low pH and high temperatures favoured for the oxidative dissolution of chalcopyrite to produce ideal conditions for jarosite precipitation. Therefore, pH must be lowered further to prevent jarosite precipitation and enhance copper recoveries from chalcopyrite in ferric media.

Submitted by Ana Hilda Fonseca (anahilda@ufba.br) on 2016-09-14T16:34:31Z No. of bitstreams: 1 Tese Mariangela V Lopes.pdf: 3032469 bytes, checksum: 36404d46d79768ab384fb49c544f496e (MD5) / Approved for entry into archive by NUBIA OLIVEIRA (nubia.marilia@ufba.br) on 2016-09-14T20:43:57Z (GMT) No. of bitstreams: 1 Tese Mariangela V Lopes.pdf: 3032469 bytes, checksum: 36404d46d79768ab384fb49c544f496e (MD5) / Made available in DSpace on 2016-09-14T20:43:57Z (GMT). No. of bitstreams: 1 Tese Mariangela V Lopes.pdf: 3032469 bytes, checksum: 36404d46d79768ab384fb49c544f496e (MD5) / Neste trabalho, foram desenvolvidos procedimentos e sistemas automatizados para o controle de qualidade de carnes e produtos cárneos quanto à presença de aditivos (NO2- e NO3-), degradação (evolução de H2S), presença de adulterante (SO3-) e riscos de contaminação pela capacidade sortiva de metais. O desenvolvimento destes procedimentos vem contrapor as metodologias clássicas recomendadas pelos órgãos oficiais brasileiros. Os métodos e procedimentos aqui desenvolvidos obedecem às recomendações da Química Analítica moderna, as quais priorizam precisão, exatidão, sensibilidade, custos operacionais, versatilidade, robustez, rastreabilidade, minimização de resíduos e produtividade analítica. O sistema de analise por injeção em fluxo (FIA), para análise seletora e discriminatória de H2S evoluído pela carne, foi desenvolvido baseado no método do azul de metileno. O emprego da multicomutação, associado à câmara de pervaporação, conferiu versatilidade ao sistema com produtividade analítica de 30 determinações h-1. Paralelo a isto, foi realizada uma avaliação da degradação de carnes empregando a espectroscopia no infravermelho próximo (NIR) para averiguação das condições de conservação de carnes. Os resultados foram concordantes para as duas metodologias (NIR e FIA), sendo possível detectar indícios de deterioração após 30 min de exposição da carne à atmosfera em temperatura ambiente. O desenvolvimento de sistema em fluxo para análise seqüencial de NO2- e NO3-, em produtos cárneos, utilizando câmara de tubos concêntricos (CTC) foi baseado no método de Greiss. A CTC proporcionou a divisão da zona da amostra, facilitando as determinações seqüenciais de NO2- e NO3-. A subzona da amostra que passava pelo tubo central da CTC resultava apenas na determinação do NO2-. A amostra que passava pelo tubo externo (coroa) da CTC, percolava grãos de cádmio coperizado, resultando na redução do NO3- existente à NO2-. Este sistema ofereceu boa sensibilidade para a quantificação dos analitos, apresentando limites de detecção de 0,018 e 0,036 mg L-1 para NO2- e NO3-, respectivamente. O procedimento proposto atingiu produtividade analítica de 120 determinações h-1. O desenvolvimento de sistema automatizado em fluxo para análise discriminatória de sulfito em carnes foi baseado no método da p-rosanilina. Foi empregado câmara de permeação gasosa, onde o SO3- presente na amostra, permeava através de membrana de PTFE para a reação com o reagente cromogênico. O sistema foi satisfatório para screening analysis, com produtividade analítica de 12 determinações h-1. A capacidade sortiva de metais pela carne bovina foi também avaliada. Foi avaliado o contato estático da carne com soluções de referência de Cd e Pb, preparadas com água de torneira, a pH 6. Foi empregada válvula multiportas, com oito canais para execução dos experimentos, enquanto que metais foram determinados por ICP OES. Os resultados indicaram um elevado poder sortivo, cerca de 80% para ambos os metais, evidenciando risco potencial de contaminação para as carnes submetidas a práticas inadequadas de abate e comercialização / In the present work automated systems and procedures to control the quality of meats and meat products had been developed, in concern to the additive presence (NO2- and NO3-), degradation (H2S evolution) and presence of adulterating species (SO32-). Also the metal sorption capacity on meat was evaluated. The development of these methods comes to oppose classical methods recommended by brazilian official agencies. The developed procedures follow the recommendations of the modern Analytical Chemical, which prioritizes the precision, exactness, sensitivity, traceability, robustness, reduced operational costs, lesser production of residue and raised analytical productivity. The flow analysis (FIA) procedure to discriminate H2S in meat sample was developed based on methylene blue method. Multicommutation, associated to gas permeation conferred versatility to the system with analytical throughput of 30 determinations h-1. Parallel to this, the spectroscopy in the near infrared region (NIR) was carried out to evaluate meat degradation. A flow system for sequential NO2- and NO3- analysis in meat products, using concentric tubes chamber (CTC) was based on the Greiss method. The CTC provides the division of sample zone, permitting the sequential analysis. The sample sub zone that passed for the central pipe of the CTC resulted in the determination of the NO2-. The sample that passed through external CCP pipe, percolated the cadmium column, allowing the reduction of the NO3- to NO2-. This system offers sensitivity in the quantification of anilities with detection limits of 0.036 for NO3- and 0.018 mg L-1 for NO2-, reaching 120 determinations h-1. The flow system for the screening analysis of SO32- in meat sample was based on p-rosanilne method. Chamber for gas permeation was employed. The system revealed efficient for screening analysis with analytical throughput of 12 determination h-1. The metal sorption capacity on meat was evaluated. The investigated species comprised Cd and Pb from solutions prepared with tap water at pH 6. In the experimental set, it was employed an eight channels multiport valve in order to prepare part of the samples, while the metal determinations was carried out by using ICP OES technique. The results obtained demonstrated an expressive retention capacity of meat for Cd2+ and Pb2+ ions with percentages ca. 80% (m/m) for both metals, indicating the potential risks related to the consumption of meat submitted to inappropriate conditions of abattoir, handling, storage and commercialization.

A produção de H2S (sulfeto de hidrogênio) é um dos principais problemas na indústria do petróleo, sendo esta uma das causas da corrosão de tanques de estocagem e tubulações. Essa produção é possibilitada devido à injeção de água do mar durante o processo de recuperação secundária do petróleo, onde alguns micro-organismos presentes nessa água, tais como as bactérias anaeróbias heterotróficas totais (BANHT) e as bactérias redutoras de sulfato (BRS), que promovem a redução do sulfato a sulfeto. Atualmente, o método de quantificação destes micro-organismos é a técnica do Número Mais Provável (NMP) que estima o resultado em aproximadamente 28 dias. No presente trabalho foi utilizada a metodologia da produção semi-contínua de sulfeto biogênico pelo período de 15 dias, com o intuito de correlacionar com os resultados das quantificações de BANHT e BRS através da técnica convencional do NMP. Foram analisadas amostras de diferentes procedências da indústria do petróleo, apresentando variação na salinidade de 0 a 16 g.L-1. O objetivo deste procedimento foi avaliar as velocidades específicas e instantâneas de produção de H2S, sugerindo, desta forma, quais amostras apresentam maior potencial para a produção biogênica de sulfeto e em quais condições essa produção se dá. Observou-se que em todas as amostras a geração do H2S se dá de forma crescente até a estabilização desta produção, sendo esta obtida quase sempre em seis dias (144h) do crescimento microbiano. A produção do sulfeto biogênico se deu de forma mais intensa nas amostras do fundo de tanque de estocagem de óleo e da água de formação. A quantificação das BANHT e das BRS foram avaliadas pelo método do NMP de acordo com a tabela de Harrigan, a qual subestima a população microbiana, desconsiderando erros provenientes da técnica / The production of H2S (hydrogen sulfide) is a major problem in the oil industry, which is a cause of corrosion of pipes and storage tanks. This production is made possible due to seawater injection during the secondary oil recovery process where some microorganisms present in this water, such as total heterotrophic anaerobic bacteria (THAB) and sulphate-reducing bacteria (SRB) that promote reduction of sulfate to sulfide. Currently, the method of quantification of these microorganisms is the technique of the Most Probable Number (MPN) which estimates the results in about 28 days. The present study used the methodology of semi-continuous production of biogenic sulfide by 15 days period, in order to correlate with the measurements results of BANHT and BRS through the conventional technique of MPN. There were several samples analyzed from different origins in the oil industry, with variations in salinity from 0 to 16 g.L-1. The purpose of this procedure was to evaluate the specific speeds and instantaneous H2S production, suggesting thereby that samples had increased biogenic sulfide production and this production conditions which occurs. It was observed that all samples in the generation of H2S occurs incrementally until stabilization of this production, these being almost always obtained in six days (144h) of microbial growth. The production of biogenic sulfide occurred more intensely in the samples of oil storage tank bottom and formation water. The quantification of SRB and THAB were evaluated by the MPN method according to Harrigan table, which underestimates the microbial population, disregarding errors arising in the art

A produção de H2S (sulfeto de hidrogênio) é um dos principais problemas na indústria do petróleo, sendo esta uma das causas da corrosão de tanques de estocagem e tubulações. Essa produção é possibilitada devido à injeção de água do mar durante o processo de recuperação secundária do petróleo, onde alguns micro-organismos presentes nessa água, tais como as bactérias anaeróbias heterotróficas totais (BANHT) e as bactérias redutoras de sulfato (BRS), que promovem a redução do sulfato a sulfeto. Atualmente, o método de quantificação destes micro-organismos é a técnica do Número Mais Provável (NMP) que estima o resultado em aproximadamente 28 dias. No presente trabalho foi utilizada a metodologia da produção semi-contínua de sulfeto biogênico pelo período de 15 dias, com o intuito de correlacionar com os resultados das quantificações de BANHT e BRS através da técnica convencional do NMP. Foram analisadas amostras de diferentes procedências da indústria do petróleo, apresentando variação na salinidade de 0 a 16 g.L-1. O objetivo deste procedimento foi avaliar as velocidades específicas e instantâneas de produção de H2S, sugerindo, desta forma, quais amostras apresentam maior potencial para a produção biogênica de sulfeto e em quais condições essa produção se dá. Observou-se que em todas as amostras a geração do H2S se dá de forma crescente até a estabilização desta produção, sendo esta obtida quase sempre em seis dias (144h) do crescimento microbiano. A produção do sulfeto biogênico se deu de forma mais intensa nas amostras do fundo de tanque de estocagem de óleo e da água de formação. A quantificação das BANHT e das BRS foram avaliadas pelo método do NMP de acordo com a tabela de Harrigan, a qual subestima a população microbiana, desconsiderando erros provenientes da técnica / The production of H2S (hydrogen sulfide) is a major problem in the oil industry, which is a cause of corrosion of pipes and storage tanks. This production is made possible due to seawater injection during the secondary oil recovery process where some microorganisms present in this water, such as total heterotrophic anaerobic bacteria (THAB) and sulphate-reducing bacteria (SRB) that promote reduction of sulfate to sulfide. Currently, the method of quantification of these microorganisms is the technique of the Most Probable Number (MPN) which estimates the results in about 28 days. The present study used the methodology of semi-continuous production of biogenic sulfide by 15 days period, in order to correlate with the measurements results of BANHT and BRS through the conventional technique of MPN. There were several samples analyzed from different origins in the oil industry, with variations in salinity from 0 to 16 g.L-1. The purpose of this procedure was to evaluate the specific speeds and instantaneous H2S production, suggesting thereby that samples had increased biogenic sulfide production and this production conditions which occurs. It was observed that all samples in the generation of H2S occurs incrementally until stabilization of this production, these being almost always obtained in six days (144h) of microbial growth. The production of biogenic sulfide occurred more intensely in the samples of oil storage tank bottom and formation water. The quantification of SRB and THAB were evaluated by the MPN method according to Harrigan table, which underestimates the microbial population, disregarding errors arising in the art