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Orientador: Celio Pasquini Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química Resumo: Imageamento hiperespectral na região do infravermelho próximo (HSI-NIR) e modelos de classificação foram empregados para a detecção de impurezas ou contaminantes em nível micro e milimétrico com mínimo preparo de amostra, como alternativa aos métodos mais trabalhosos e subjetivos comumente usados em dois tópicos de relevância social e técnico-científica. O primeiro tópico está relacionado à preocupação global da poluição por microplásticos (MP), demandando o desenvolvimento de método analíticos. Modelos quimiométricos foram desenvolvidos por Modelagem Independente por Analogia de Classe (SIMCA) para identificar MP das classes polietileno (PE), polipropileno (PP), poliamida-6 (PA), tereftalato de polietileno (PET) e poliestireno (PS) em areia de praia com mínimo preparo de amostra. Um conjunto de dados espectrais abrangentes, incluindo aqueles de polímeros prístinos, formulados e degradados, foi usado para construir os modelos. A sensibilidade e especificidade dos modelos foram superiores a 99% para todas as classes. Foram validados com centenas de MP primários e secundários coletados no ambiente. O efeito do tamanho da partícula, cor e degradação na previsão dos modelos são discutidos. O método foi aplicado a amostras ambientais, identificando milhares de partículas sem prévia inspeção visual, o que é uma contribuição para melhorar a produtividade na detecção e confirmação de MP. No segundo tópico é descrita uma proposta de um método rápido para a determinação do máximo permitido de 1% m/m de impurezas em café torrado e moído, realizando análises diretas por HSI-NIR. Foram desenvolvidos quatro modelos de classificação por Análise Discriminante por Mínimos Quadrados Parciais (PLS-DA) para as classes de café e impurezas, obtendo-se de 97 a 99 % de especificidade e sensibilidade para todos os modelos, apesar da similaridade espectral entre as espécies e região espectral ruidosa e nos limites instrumentais da técnica. Os resultados de previsão da classificação foram utilizados para quantificação pela razão entre os pixels da imagem classificados como impurezas e o total de pixels da imagem (Porcentagem de Pixels de Impureza, PPI). Demonstrou-se o efeito de bordas nas interfaces entre espécies de diferentes classes na previsão e contagem de pixels. Embora as impurezas tenham sido identificadas nos mapas químicos, os valores de PPI não se mostraram repetitivos para diferentes amostras com o mesmo teor em massa de impureza e a granulometria do café foi a principal causa. Demonstrou-se limitações em relação ao uso de imagens em análise direta quantitativa de sólidos segregados Abstract: Near-infrared hyperspectral imaging (HSI NIR) and chemometric classification models were applied for the detection of impurities or contaminants at the micro and millimeter level with minimal sample preparation, as an alternative to the more laborious and subjective methods commonly used, in two topics of societal and technical-scientific relevance. The first topic is related to the global concern of microplastic (MP) pollution, and there is the demand for the development of analytical methods to detect them. The use of HSI-NIR combined with Soft Independent Modelling of Class Analogy (SIMCA) is described to automatically identify MP of the classes polyethylene (PE), polypropylene (PP), polyamide 6 (PA), polyethylene terephthalate (PET) and polystyrene (PS) in beach sand with minimum sample preparation. An in-house comprehensive spectral dataset, including from pure to weathered MP, was used to build the classification models. SIMCA sensitivity and specificity were over 99 % for all classes. Models were validated with hundreds of primary and secondary MP collected in the environment. The effect of particle size, color and weathering are discussed. The method was applied to environmental samples, identifying thousands of particles without prior visual sorting, which is a time-efficiency method contribution. The second topic describes the proposal for a fast method for the determination of the maximum allowed 1% w/w of impurities in roasted and ground coffee, through sample direct analysis by HSI-NIR. Four classification models using Partial Least Squares Discriminant Analysis (PLS-DA) were developed for coffee and impurities classes, obtaining from 97 to 99% specificity and sensitivity for all models, despite the spectral similarity between species, noisy spectral region and within the technique instrumental limits. The classification prediction results were used for quantification by the ratio between the image pixels classified as impurities and the total image pixels (Percentage of Impurity Pixels, PPI). The effect of edges at the interfaces between species in predicting and counting pixels of different classes was demonstrated. Although impurities have been identified at the chemical maps, the PPI values were not repetitive for different samples with the same impurity mass content, and coffee granulometry was the main cause. Limitations regarding the use of images in direct quantitative analysis of segregated solids were demonstrated Doutorado Química Analítica Doutora em Ciências CNPQ 465768/2014-8 CAPES 001 FAPESP 2014/50951-4

Orientador: Isabel Cristina Sales Fontes Jardim Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Química Resumo: Fases sólidas fluoradas apresentam características oriundas das propriedades da ligação C-F, como o alto momento de dipolo e a baixa polarizabilidade e isto confere seletividades peculiares a elas. Existem diversas fases estacionárias alquilperfluoradas e fenilperfluoradas comerciais para cromatografia líquida, entretanto, a oferta de fases sólidas fluoradas para extração em fase sólida (SPE) é menor. Assim, este trabalho descreve um novo método de SPE utilizando uma fase fluorada preparada pela sorção e imobilização térmica de um polissiloxano [poli(metil(3,3,3-trifluoropropil)siloxano], sobre sílica de 30-75 µm, resultando na fase sólida não capeada (FNC) e após reação química apropriada, resultando na fase capeada (FC). Os preparos foram realizados com êxito, confirmado através da caracterização da fase por espectroscopia de absorção no infravermelho, análise elementar e ressonância magnética nuclear. Para estudar o desempenho das fases sólidas fluoradas, escolheram-se compostos com estruturas químicas apropriadas para a retenção esperada, i.e., com grupos funcionais de alta densidade eletrônica. Para tanto, escolheram-se alguns pesticidas (atrazina, imidacloprido, bromacila e outros das classes dos organofosforados, triazóis e estrobilurinas) e compostos perfluorados. Além das estruturas, estes compostos também foram escolhidos por serem contaminantes ambientais. Um método cromatográfico utilizando LC-ESI-MS/MS foi desenvolvido e validado para a determinação dos compostos escolhidos. Quando as condições otimizadas de SPE foram aplicadas a amostras ambientais, conseguiram-se recuperações acima de 60 % para oito pesticidas, no nível de concentração de 1 ng/mL. Atingiu-se uma eluição seletiva dos compostos perfluorados, em que estes foram separados dos demais compostos em diferentes alíquotas de eluição. Desta forma, a fase sólida fluorada apresentou-se como uma alternativa viável para a determinação dos compostos estudados e pôde ser aplicada com sucesso na extração destes compostos. A característica que ficou mais evidente foi a alta retenção que ela apresentou aos compostos estudados, comportamento o qual pode ser expandido para compostos similares Abstract: Fluorinated solid phases can present unique selectivity due the special properties of the C-F bonds, such as high dipole moment and low polarizability. There are several commercial alkyl and phenylperfluorinated stationary phases for liquid chromatography. However, the availability of fluorinated solid phases for solid phase extraction (SPE) is still low. This work describes a new solid phase and extraction method using a fluorinated sorbent prepared by sorption and thermal immobilization of a fluorinated polysiloxane, namely poly[methyl(3,3,3-trifluoropropyl)siloxane], onto silica of 30-75 µm particle size. This procedure was successful and confirmed through the characterization made by infrared spectroscopy, nuclear magnetic resonance and elemental analysis (C, H, N). The performance of the fluorinated solid phase was studied by choosing compounds with suitable chemical structures to meet the expected retention, i.e. with functional groups that have high electronic density. The pesticides chosen were atrazine, imidacloprid and bromacil and the profenofos, triazols and strobilurins classes. In addition to the structures, these compounds were also chosen because they are environmental contaminants. A chromatographic method using LC ESI MS/MS was developed and validated for the determination of the chosen compounds. When the optimized SPE conditions were applied to environmental samples, recoveries above 60% were achieved for eight pesticides, at the 1 ng/mL concentration level. Selective elution of the perfluorinated compounds was achieved, in which they were separated from other compounds in different aliquots of elution. Thus, the fluorinated solid phase presented itself as a viable alternative for determining the compounds studied and could be successfully applied in the extraction thereof. The most evident feature was the high retention that the phase presented for the studied compounds, behavior which can be expanded to similar compounds Mestrado Química Analítica Mestra em Química

The study of wood chemistry to explain the response of trees to climate variation is efficient for retrospective analysis of changes induced in wood during the process of adaptation to seasonal variations. Hyperspectral imaging (HSI) in near infrared could be useful for prediction of several wood chemical components. The objective is understand how water constraints influence wood formation. Wood disks of E. grandis clone from six treatments (100% and 65% of rainfall crossed with potassium and sodium fertilizations) were sampled. HSI were obtained on transversal section of the disks using a line scan hyperspectral camera from 1000-2500 nm with a pixel size of 625 x 625 µm. For calibration, were selected 60 wood solid samples from an Eucalyptus collection, which were measured the total extractive values. HSI or these samples were acquired from transversal section with the same camera. We regressed the mean spectra for each sample with extractives values by Partial Least Square Regression. Due to the model, the total extractives for each pixel to produce an image for the wooden disks were predicted. Based on them, the total extractive distribution according to growth conditions were compared. revealing that trees under stress conditions show a higher heterogeneous chemical profile from the pith to bark. Eucalyptus demonstrates sensitive precipitation variations. with rapid growth and considerable increase in DBH during rainy seasons and the reverse in drought. Consequently, is possible to discriminate different patterns of chemical compound distribution according to the growth conditions.

The aim is to study tree development submitted to different water and mineral constraints. The objective is to correlate spatial distribution of wood chemistry with wood density secondary growth. We sampled wood discs from 54 trees in rainfall exclusion design with Eucalyptus grandis at Esalq-USP. ltatinga Station.brazil. We felled the 5 years old trees growing under different water availability. For each disk. we acquired an image with a near infrared (nir) hyperspectral camera (hs1, specim. pixel size 625 x 625µml. The challenge here was to transfer our previous nir calibrations for total extractives built with a benchtop spectrometer (vector. bruker) to a hsi camera by using standard sample set measured ,>n the two devices. An efficient model were built for the his camera with a prediction error of 10.3% compared to the prediction error of 11.60% for our previous calibration with benchtop spectrometer. Then, based on spectra from his image. we predicted extractive contents and built images. These allow us to compare their spatial distributions according to the growth conditions. In the absence or absence or fertilization, trees with higher water stress showed a higher heterogeneous distribution. from pith to bark, for the total extractive contents and a higher average mean value. In perspective. these data will allow us to study and reline the knowledge on cambium activity according to climatic variations by crossing variability of the chemical properties, x-ray micro-density and anatomy of wood, and diameter growth rate measured by electronic dendrometers.

Most near-infrared spectroscopy (NIRS) studies for wood density use multiple spectral acquisitions taken manually at several points from pith to bark. Recently the use of near-infrared hyperspectral imaging (NIR- HSI) has shown good performance in predictions of wood properties allowing build high spatial resolution predictive images. The combined use of NIR-HSI and X-ray microdensity imaging (X-ray MDI) could be more practical for evaluation of spatial variation of wood density. The aim was to develop a wood density calibration model for NIR-HSI (625 µm pixel size) from X-ray MDI (30 µm pixel size) and evaluate the spatial variation of wood density along stem cross-section in Eucalyptus grandis trees. Wood discs were collected from 18 trees of 6 years old, submitted to two different water availability, located in Sao Paulo. Brazil. The challenge here was to match the pixels of X-ray MDI to pixels of NIR-HSI (in 2 mm width radial region) to transfer accurate values of wood density to each, pixel of NIR-HSI. The R2 of the model was 0. 72, while the root mean squared error was and 4.8 x 10-2 g cm-3 for the validation group. The prediction model allows comparing their spatial distributions according to the growth conditions. Trees with higher water stress showed higher wood density. Treatments showed a similar spatial variation or wood density. increasing from pith to bark. In perspective, these data will allow evaluating the spatial distribution of wood density inter and intra-tree rings in relation to meteorological variability.

Tese (doutorado) - Universidade Federal de Santa Catarina, Centro de Comunicação e Expressão. Programa de Pós-Graduação em Estudos da Tradução Pesquisas diversas sobre games comerciais têm pululado no decorrer das últimas décadas e coberto uma miríade de tópicos - entre eles, os letramentos através de games (BUCKINGHAM & BURN, 2007; SQUIRE, 2008; SALEN, 2007) e os princípios de aprendizagem embutidos em bons games (GEE, 2003). No entanto, há uma escassez de trabalhos relacionando games e a aquisição de segunda língua (DEHAAN, 2005, 2008). A presente tese investiga a aquisição de elementos linguísticos de segunda língua no domínio semiótico de games comerciais. Dois estudos exploratórios foram projetados: o estudo 1 com dois games série Need for Speed: Underground e o estudo 2 com o game The Sims. A sinergia visualverbal (KRESS, 2000) foi explorada nos testes de tradução com e sem screenshots dos games Need for Speed: Underground e nas paráfrases do game The Sims. A análise dos dados se apoderou de alguns conceitos teóricos do modelo funcionalista de tradução de Christiane Nord (1997). Os resultados de ambos os estudos exploratórios confirmam a aquisição de alguns elementos linguísticos essenciais para a progressão nos games investigados Many academic works on commercial off-the-shelf computer games have appeared over the last decades investigating a myriad of topics such as game literacy (BUCKINGHAM & BURN, 2007; SQUIRE, 2008; SALEN, 2007) and the learning principles that good games incorporate (GEE, 2003). However there is a lack of academic works on computer games and second language acquisition (DEHAAN, 2005, 2008). The present thesis examines the acquisition of linguistic elements of a second language in the semiotic comain of commercial games. To this end, two exploratory studies were designed: the first with the two games of the series Need for Speed: Underground and the second with the game The Sims. The visual-verbal synergy (KRESS, 2000) was explored in two translation tests: with and without screenshots of the game series Need for Speed: Underground and in the paraphrases of the game The Sims. The data analysis made use of some of the theoretical concepts from Christiane Nord#s functionalist model (1997). The results of both studies confirm the acquisition of some linguistic elements that are pivotal for progressing within the games investigated