Embora o uso de etanol como combustível venha aumentando no Brasil e em diversos países, há uma grande escassez de dados relacionados à abundância desse álcool e de espécies orgânicas correlatas na atmosfera. O estudo temporal do comportamento do etanol em água de chuva no Brasil é pioneiro, e serve de base para melhor compreender as alterações que possam ocorrer na atmosfera devido ao aumento do uso desse combustível. Neste trabalho foi desenvolvido um novo método utilizando headspace GC-FID para a determinação simultânea de acetaldeído (AA), acetona (AC), metanol (MeOH) e etanol (EtOH), em concentrações ambientalmente relevantes em águas naturais. O método é mais simples do que aqueles apresentados na literatura, robusto e de custo relativamente baixo. O método apresentou boa recuperação, precisão, e sua exatidão foi comprovada pela forte correlação com o método que utiliza HPLC, e que já é bem estabelecido. A concentração de etanol foi determinada em amostras de água de chuva de Ribeirão Preto coletadas de 2012 a 2016 (n = 186). A média ponderada pelo volume (MPV) foi de 5,28 ± 0,49 µmol L-1, que é próxima da concentração esperada no equilíbrio entre a fase gasosa e aquosa. Esse valor de etanol é cerca de 28 vezes maior do que a média encontrada na cidade de Wilmington (EUA), refletindo o elevado uso de etanol combustível no Brasil. As concentrações médias anuais de etanol na chuva nos mais de 4 anos de estudo variaram pouco, e também não apresentaram diferenças significativas de acordo com a estação do ano, sazonalidade das atividades agrícolas, ou com a direção das massas de ar. Para as amostras de água de chuva coletadas de fevereiro a dezembro de 2016 a concentração MPV das espécies analisadas foram: 0,84 ± 0,12 µmol L-1 AA (n= 62); 0,70 ± 0,08 µmol L-1 AC (n = 59);10,9 ± 1,19 µmol L-1 MeOH (n = 62), 15,8 ± 1,64 µmol L-1 ácido fórmico (n = 67); e 9,76 ± 0,95 µmol L-1 ácido acético (n = 67). A massa média de carbono orgânico identificado nas amostras representou cerca de 20% do total de carbono orgânico dissolvido (COD) na água de chuva. O fluxo estimado de carbono orgânico por deposição úmida foi de 5,1 g C m-2 ano-1, sendo 1,0 g C m-2 ano-1identificados neste trabalho. Além da emissão veicular, uma importante fonte de COD para a atmosfera é a queima de biomassa, que ainda ocorre com frequência no estado. As ferramentas estatísticas aqui utilizadas considerando as espécies orgânicas identificadas juntamente com outras espécies inorgânicas majoritárias, não permitiram separar claramente as fontes predominantes de emissão na região. Isso deve ocorrer porque a emissão veicular durante todo o ano é predominante com relação às possíveis emissões biogênicas e por queima de biomassa. A exposição de amostras de água de chuva à irradiação com luz solar artificial mostrou que houve perda de EtOH e formação de AA, porém os processos não ocorreram em proporção estequiométrica, e nem na mesma taxa. No caso do MeOH e formaldeído, a formação e perda dessas espécies ocorreram de forma errática. A ausência de uma tendência clara nas transformações fotoquímicas dos álcoois reflete a complexidade da matriz e das reações envolvidas na atmosfera. / Although there has been a dramatic increase on the use of ethanol fuel in Brazil and in several other countries, there is a great lack of data related to the abundance of ethanol and associated organic species in the atmosphere. The temporal study of the behavior of ethanol in rainwater in Brazil is pioneer, and may serve as a basis to better understand the changes that occur in the atmosphere due to the increasing use of this fuel. This work presents a new headspace GC-FID method to simultaneously determine acetaldehyde (AA), acetone (AC), methanol (MeOH) and ethanol (EtOH) at environmentally relevant concentrations in the atmosphere and in a variety of natural waters. The method is simpler than those presented in the literature, robust and relatively low-cost. The method presented good recovery, precision and good agreement with a HPLC method for determination of acetaldehyde, methanol, and ethanol, which endorsed the accuracy of the proposed method. The ethanol concentration was determined in rainwater samples from Ribeirão Preto from 2012 to 2016 (n = 186). The volume-weighted mean (VWM) was 5.28 ± 0.49 mol L-1, which is close to the expected concentration at the equilibrium between the gas and aqueous phases. The ethanol value is about 28 times higher than the average found in the city of Wilmington (USA), reflecting the high use of ethanol fuel in Brazil. The annual mean concentrations of ethanol in rainwater samples over 4 years of monitoring varied little, and also did not show significant differences according to the season, agricultural activities, or the direction of the air masses. For the rainwater samples collected from February to December 2016 the VWM concentration of the other analyzed species were: 0.84 ± 0.12 mol L-1 AA (n = 62); 0.70 ± 0.08 mol L-1 AC (n = 59), 10.9 ± 1.19 mol L-1MeOH (n = 62), 15.8 ± 1.64 mol L-1formic acid (n = 67); and 9.76 ± 0.95 mol L-1 acetic acid (n = 67). The identified organic carbon average mass in the samples represented about 20% of the total dissolved organic carbon (DOC) in rainwater. The estimated flux of organic carbon by wet deposition was 5.1 g C m-2 year-1, being 1.0 g C m-2 year-1 identified in this work. In addition to the vehicular emission, an important source of DOC to the atmosphere is the biomass burning, which still occurs frequently in the state. The statistical tools used here, considering the organic species identified together with other major inorganic species, did not allow to clearly separate the predominant emission sources in the region. This may occur because the year-round vehicular emission is predominant in relation to the possible biogenic and by biomass burning emissions. Exposure of rainwater samples to irradiation with artificial sunlight showed that there was loss of EtOH and formation of AA, but the processes neither occurred in stoichiometric proportion, nor at the same rate. In the case of MeOH and formaldehyde, the formation and loss of these species occurred erratically. The absence of a clear trend in the photochemical transformations of alcohols reflects the complexity of the matrix and the reactions involved in the atmosphere.

A determinação de valores de referência de alguns xenobióticos naturalmente existentes no organismo é importante na biomonitorização, para comparação de níveis encontrados na população exposta com os da população de referência. A acetona é um solvente muito popular, utilizado em vários ramos da indústria e em laboratórios químicos. O isopropanol é um solvente largamente utilizado em indústrias, laboratórios e está presente em vários produtos domésticos. Este solvente é biotransformado no organismo humano, tendo como principal metabólito a acetona. A acetona em urina (AcU) é o bioindicador mais usado para avaliar a exposição de trabalhadores expostos a acetona e ao isopropanol. Como também é encontrada em pessoas não expostas ocupacionalmente a estes solventes, o objetivo deste trabalho foi verificar os níveis basais de AcU e a possível influência de fatores individuais nestes níveis. A população de referência foi constituída por 207 indivíduos (91 homens e 116 mulheres, com idades entre 18 e 80 anos). A AcU foi determinada por headspace/cromatografia em fase gasosa/DIC. O método mostrou linearidade de 0,1 a 5,0 mg/L; o limite de detecção e de quantificação de 0,1 mglL; precisão intra-ensaio, entre 4 e 5% e inter ensaio, entre 5,2 e 8,8% (urina sem adição e fortificada com 1,0 e 3,0 mgIL de acetona). Para a população total, os valores de referência encontrados foram: média (&#177;DP) de 1,12 (&#177;0,47) mgIL; mediana de 1,04 mgIL; média geométrica de 1,03 mglL; intervalo de confiança 95% entre 0,98-1,26 mglL e valor superior de referência (média + 2DP) de 2,06 mgIL. Devido ao fato da distribuição dos valores de AcU (mgIL) não ser Gaussiana, optou-se por uma transformação dos valores (Iog AcU) que aproximou os dados da distribuição normal ( W = 0,98532, P < 0,7000). A população selecionada demonstrou ser saudável e adequada ao estudo; o sexo e a ingestão de bebidas alcoólicas parecem afetar os teores de acetona urinária, enquanto a idade e o uso de tabaco não mostraram este efeito. / The determination of reference values of some xenobiotics is important for the biomonitoring, to compare the concentration in the exposed and the general population. The acetone is a very popular solvent, that is used in a large number of industries and laboratories. Isopropanol is used in industries, laboratories and cosmetic products. In the human body, this solvent is metabolized and the most important product is acetone. Acetone in urine (AcU) is the most used biomarker to monitore workers exposed to acetone/isopropanol. This substance is also found in non-exposed people, so, the main objective of this work was to verify the basal levels of AcU and if there are some factors that have influence on these levels. 207 volunteers were studied (91 men and 116 women, and the ages between 18-80 years). The AcU was determinated by headspace/gas chromatography/ FID. The method showed linearity between 0.1-5.0 mg/L; limit of detection (LOD) and limit of quantification of 0.1 mglL; intra-assay precision, between 4 and 5%; inter-assay precision, between 5.2 and 8.8% (urine without addition, and spiked 1.0 and 3.0 mg/L of acetone). In the total population, the reference values obtained were: mean (&#177;SD) 1.12 (&#177; 0.47) mg/L; median 1.04 mg/L; geometric mean 1.03 mg/L; 95% confidence range between 0.98-1.26 mg/L and upper reference value (mean + 2 SD) of 2.06 mg/L. The values distribution wasn\'t \"normal\", therefore, the ,transformation of the values was necessary (109 AcU). Sex and alcohol intake showed significant influence on the concentration of acetone in urine. No interference was verified for smoking or the age of the volunteers.

This thesis deals with the stopping of hydration of alkali activated slag by organic solvents and investigates to what extent the selected organic solvent affects the results of the analyses. The solvents used were acetone, diethyl ether, ethanol, isopropanol and methanol, and this is because these are the most commonly used organic solvents in practice. Thermogravimetric analysis along with differential thermal analysis was used to assess the degree of influence of organic solvents on the alkali activated slag and Portland cement samples. Methanol and acetone affected the samples the most and the longer the sample was stored in the solvent, the more it reacted with the organic solvent. The adverse interaction of organic solvent was greatest for the Portland cement samples. Samples that were rinsed with diethyl ether prior to analysis had lower mass losses than samples that were not rinsed. In the case of alkali activated slag, it was found that the way in which the thermogravimetric results were affected by organic solvents was highly dependent on the activator used, with the smallest effect observed for Na2CO3 activation, while the largest effect was observed for NaOH activation at temperatures below 600 °C, and for higher temperatures for water glass activation.

In this work, we use pulsed-field gradient (PFG) NMR to probe molecular diffusion of liquids inside mesoporous structures and assess the influence of surface modifications, namely, deposition of palladium (Pd) nanoparticles over alumina (Al2O3) surfaces and passivation of titania (TiO2) surfaces with alkyl chains, on the diffusion pattern.

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This thesis describes the preparation and characterization of manganese oxide catalysts and their application in the oxidation of acetone, a typical volatile organic compound (VOC), and ozone decomposition. This topic is of great value because of environmental concerns of the elimination of the harmful VOCs and ozone. Manganese oxide was chosen because it is a well-known complete oxidation catalyst for VOCs and also an active catalyst for ozone decomposition. Two cases of studies were carried out in this work. The first study involved the oxidation of acetone using ozone on silica- and alumina-supported manganese oxide catalysts deposited on aluminum oxide foam substrates. The characteristics of the catalysts were determined through various techniques, including x-ray diffraction (XRD), x-ray absorption spectroscopy (XAS), Brunauer-Emmett-Teller (BET) surface area analysis, temperature-programmed reduction (TPR), and oxygen chemisorption. The use of these techniques allowed better understanding of the nature of the catalysts. Activity tests were carried out in the acetone oxidation reaction and it was found that the usage of ozone substantially reduced the oxidation temperature. Steady-state in situ Raman spectroscopy was also carried out to better understand the mechanism of the acetone oxidation reaction using ozone. The second study involved an investigation of structural and electronic properties of manganese centers of the MnOx/SiO2 and MnOx/Al2O3 catalysts during the ozone decomposition reaction using in situ x-ray absorption spectroscopy (XAS). The number of surface active sites was again determined through TPR and oxygen chemisorption measurements. The performance of the catalysts with different loadings and supports were also compared. / Master of Science

Grape pomace (GP) is one of the most abundant and underutilized fruit-derived wastes. GP is generated during winemaking, occupying over 60% of the total solid winery wastes. GP may cause serious environmental problems if it is not properly handled. On the other hand, it is rich in valuable compounds that are worthy of recovery. Although research has been working on GP upgrading, the utilizations are limited to producing a single product (e.g., grape seeds oil or polyphenol powders), which leads to large volumes of secondary wastes left. Therefore, the goal of this study is to develop an integrated process for the comprehensive utilization of GP by the production of multiple value-added products and evaluate its economic feasibility at a commercial scale. First, the chemical composition of different industrial GPs was analyzed to lay the foundation for the process design. Based on the analyzed chemical composition, an integrated process was developed to produce grape oil, polyphenols, and biofuels from GP. In this process, GP was extracted by hexane to produce oil, followed by aqueous ethanol solution extraction to obtain polyphenols. The solid residue rich in structural carbohydrates was then pretreated by alkali to partially remove lignin and enzymatically hydrolyzed to produce monomer sugars. The produced sugars were used as feedstock to produce acetone, butanol and ethanol (ABE) through anaerobic fermentation. Under the optimized conditions, the process was able to produce 71.9 g crude oil, 322.8 g crude polyphenols (equivalent to 72.6 g gallic acid), and 20.7 g ABE from 1 kg dry GP. Besides the valuable products, the process co-generated a large amount (50% of input GP biomass) of secondary waste, which is rich in lignin. Therefore, we further converted the secondary waste to biochars and evaluated their potential application in water purification by removing lead (Pb) from contaminated water. Based on the results, the produced biochar showed a high Pb adsorption ability (134 mg/g), with 66.5% of lead removal achieved within the first 30 min. Experimental and modeling results indicated that both physisorption and chemisorption mechanisms were involved in the Pb adsorption of the biochar. Finally, techno-economic analysis was conducted to evaluate the economic feasibility of the integrated processing of GP into oil, polyphenols, and biochar at an industrial scale. The results showed that compared with generating of single product or dual products, the integrated process aiming to produce multiple products had the best economic performance with the net present value (NPV), internal rate of return (IRR), and payback period of $135.0 million, 47.5%, and 1.8 years, respectively. Sensitivity analysis showed that plant capacity and polyphenol selling price had major impacts on process economics. Therefore, a suggestion for implementing this integrated process is to invest more in the polyphenol production and purification process to generate high-quality polyphenols with a high selling price and running the plant with a large capacity. Overall, we explored a novel integrated process that aims to produce multiple value-added products to increase the economic gain for the wine industry, and at the same time, potentially reduce the environmental burdens caused by GP disposal. / Doctor of Philosophy / During wine making, a large amount of solid waste is generated, and the major one is called grape pomace (GP). GP is mainly consisted of grape skins, seeds, and some stems. Normally, GP is discarded as waste; however, if it is not handled properly, GP may cause serious damages to the environment such as contaminating soil and stream water. On the other hand, GP has valuable compounds that could be recovered for other applications. Previous researchers used GP to produce a single product, which still leads to a large amount of components not used. Therefore, the aim of the current study is to design a process to comprehensively utilize GP to produce multiple value-added products. The developed process can produce grape seed oil, polyphenols, and biofuels from GP. The solid residue generated from the designed process was further converted into biochar, which can be used as an excellent adsorbent to remove lead (Pb) from contaminated water. Based on the economic model results, the developed process to convert GP into grape seed oil, polyphenols, and biochar could be a promising investment at an industrial scale. Generally speaking, various valuable products were obtained from low value GP waste, which could not only reduce the potential environmental problems caused by waste disposal, but also provide different value-added products for food, pharmacy, chemical, and energy industries.

A insuficiência cardíaca é uma síndrome clínica de alta morbimortalidade e por este motivo é crescente o interesse em se estudar novos biomarcadores da doença visando buscar caminhos para novas estratégias terapêuticas. Neste contexto, a análise do ar exalado pode ser promissora. Baseado nestes dados e na observação de que pacientes com insuficiência cardíaca grave exalam odor peculiar, ainda em estudo piloto, nós identificamos acetona no ar exalado de pacientes com insuficiência cardíaca. Assim, nosso estudo teve por objetivo primário avaliar o papel da acetona exalada como biomarcador do diagnóstico de insuficiência cardíaca e de insuficiência cardíaca descompensada. Como objetivo secundário, avaliar sua relação com a classe funcional segundo a classificação da New York Heart Assocation (NYHA) e sua correlação com o peptídeo natriurético do tipo B (BNP). Entre maio de 2009 e setembro de 2010, pacientes consecutivos com disfunção sistólica (grupo IC) admitidos na emergência (insuficiência cardíaca descompensada grupo ICDESCOMP) e pacientes estáveis nos últimos três meses encaminhados para o teste cardiopulmonar (insuficiência cardíaca compensada grupo ICCOMP) foram submetidos à coleta de ar exalado (extração em água) para posterior análise qualitativa por cromatografia gasosa acoplado à espectrometria de massas e quantificação por espectrofotometria de absorção, através da reação com salicilaldeído. Entre os 235 pacientes avaliados, 89 foram incluídos (59 com insuficiência cardíaca descompensada e 30 com insuficiência cardíaca compensada), 61% do sexo masculino e com mediana de idade de 52 anos. Vinte indivíduos saudáveis (grupo controle) pareados por idade participaram do estudo. O valor mediano (intervalo interquartil) de acetona exalada foi maior no grupo IC em relação ao controle [3,70 g/L (1,69-10,45 g/L) versus 0,39 g/L (0,30-0,79 g/L), p < 0,001]. O valor mediano de acetona em pacientes com insuficiência cardíaca descompensada foi maior do que no grupo com insuficiência cardíaca compensada [7,80 g/L (3,60-15,20 g/L) versus 1,22 g/L (0,682,19 g/L), p < 0,001]. A acurácia do método tanto para o diagnóstico de insuficiência cardíaca (acetona > 1,16 g/L; área sob a curva = 0,94) quanto para o diagnóstico de insuficiência cardíaca descompensada (acetona > 2,50 g/L; área sob a curva = 0,93) foi aproximadamente 85 %, semelhante à acurácia do BNP (BNP > 42 pg/mL; área sob a curva = 0,97 e BNP > 424 pg/mL; área sob a curva = 0,94, respectivamente). Houve correlação positiva entre acetona exalada e BNP (r = 0,772, p < 0,001). Observamos aumento progressivo nas concentrações de acetona exalada de acordo com a piora da classe funcional segundo NYHA (p < 0,001). Assim, podemos concluir que nosso estudo revelou a acetona exalada como um novo biomarcador do diagnóstico de insuficiência cardíaca e de insuficiência cardíaca descompensada, que está associado à maior gravidade da doença e que apresenta correlação positiva com BNP. Sua dosagem é um novo método de diagnóstico não invasivo que pode ser realizado à beira leito, cuja acurácia é semelhante à do BNP / Heart failure (HF) is a condition associated with high mortality and frequent hospital admissions. In this context, multiple biomarkers of heart failure severity have emerged recently. However, the usefulness of most of these biomarkers has not been fully established. Exhaled breath has been considered a suitable tool (biomarker) to evaluate different diseases. Based on the clinical observation that patients with acute decompensated heart failure (ADHF) exhale a distinct odor, in a pilot study we have identified acetone in exhaled breath of heart failure patients and this study aimed to evaluate the role of acetone as a new biomarker of heart failure and ADHF disease. As secondary aims, we intended to analyze the relation to New York Heart Association (NYHA) class and the correlation with B-Type Natriuretic Peptide (BNP). Patients with systolic dysfunction (HF group) admitted consecutively at the emergency room (ADHF group) and stable patients referred to the cardiopulmonary test (chronic HF CHF group) between May 2009 and September 2010 were submitted to exhaled breath collection (extraction into water). Acetone identification was done by gas chromatography-mass spectrometry (GC-MS) and its determination by absorption spectrophotometry after reaction with salicylaldehyde. Twenty healthy subjects matched for age were enrolled (control group). Among 235 patients with HF, 89 were included in the study (59 ADHF and 30 CHF), 61% male, with median age of 52 years. Median exhaled breath acetone value (interquartile range) was higher in the HF group when compared to control group [3.7 g/L (1.69-10.45 g/L) versus 0.39 g/L (0.30-0.79 g/L), p < 0.001] and also higher in ADHF when compared to CHF group [7.80 g/L (3.60-15.20 g/L) versus 1.22 g/L (0.682.19 g/L), p < 0,001]. The accuracy of the method to diagnose CHF (Acetone > 1.16 g/L; AUC = 0.94) and ADHF (Acetone > 2.5 g/L; AUC = 0.93) was similar to the accuracy of BNP (BNP > 42 pg/mL; AUC = 0.97 and BNP > 424 pg/mL; AUC = 0.94, respectively). There was a positive correlation between exhaled breath acetone and plasmatic BNP (r = 0.772, p < 0.001). Levels of exhaled breath acetone were different among the four different NYHA classes (p<0.001). In summary, we can conclude that our study showed exhaled breath acetone as a new biomarker of heart failure and ADHF. It is associated with heart failure severity and has a good correlation with BNP. This is a promising non-invasive diagnostic method of heart failure, whose accuracy is equivalent to BNP