This thesis deals with methological issues in the study of chemical exposure and sick building syndrome (SBS). SBS is a combination of general, mucosal and skin symptoms that some people experience when staying in specific buildings. The aim was to find chemical patterns associated with SBS, but also to address methological problems in such study. The plan was to conduct a case-control study comparing the two groups’ chemical exposure, where cases were defined as those having at least one general, one mucosal and one skin symptom each week the last three months. For the planning it was necessary to know if cases and controls could be selected from the same building. If everyone in a building have the same chemical exposure it is no use to compare exposure between two persons at the same workplace. In the first paper exposure to more than 100 compounds is compared between 79 participants working in eight buildings. It was found that for the majority of compounds the variation in exposure was larger within buildings than between buildings, which means that cases and controls could be allowed to work in the same building. The second paper is a comparison of three adsorbents usability in finding differences in chemical exposure between SBS cases and controls. This was done by using chemometrical methods but comparisons of sampled amounts, blank values and reproducibility were also done. Tenax TA was found to be the best adsorbent, hence used in the case-control study. In recent years ozone and ozone reaction products with unsaturated volatile organic compounds (VOCs) has been in focus. Nitrogen dioxide is another gas affecting oxidation of reactive VOCs. Formaldehyde is an irritant formed when unsaturated VOCs are oxidised, and in some studies a relation with SBS has been found. In paper three the relation between personal exposure to formaldehyde, nitrogen dioxide, ozone, terpenes and SBS has been investigated among more than 200 office workers in a case control study in Umeå and Vasa. Cases (based on symptoms during the week of measurements) had lower ozone exposure than controls. No further associations were found at present exposure levels. A planed analysis of relations to VOCs could not be done due to analytical problems, and problems due to difficulties with consistent identification of compounds in a very large data set. These problems are further discussed in the thesis. In the case-control, study participants answered questionnaires about symptoms during "the past three months", "right now" (when answering the questionnaire), and during the week of exposure measurements. In the fourth paper the stability of symptoms were compared by answers at different occasions. It was found that the case/control concept was as stable as individual symptoms. More participants with atopic disease and those 41 years old or younger changed class compared with those without atopic disease and older participants. Measurement activities appeared to make participants report more symptoms. Fatigue, dry eyes and dry skin are suggested to be symptoms with strongest, and illness/dizziness to be weakest association with IAQ. / KLUCK-projektet

The sick building syndrome (SBS) comprises eye, nose, skin, and throat symptoms, headache and fatigue. Gender, personality aspects, and psychosocial factors at work have lately been at focus in health research. The main aim of this thesis was to investigate the relationships between SBS and personal factors, personality traits, and psychosocial work stress. Two different populations were studied: a cohort of 195 subjects working in suspected “sick buildings” followed 1988-1999, and a random sample of 695 subjects from the Swedish population, 20-65 y. Two personality scales were used; the Karolinska Scales of Personality (KSP) and the Sense of Coherence (SOC). Two stress questionnaires were used: the 3-dimensional demands-control-support model (DCS) and the Assessment of Perceived Psychosocial Work Environment (PPWE). SBS and personal factors were assessed by a postal symptoms questionnaire and a symptom score (SC) was calculated. Personality was assessed by means of two verbal personality scales, the KSP and the SOC. Females in problem buildings had more SBS than men, and females had a lower SOC and more anxiety and aggressivity in the KSP. Females and males in the general working population reported differences in psychosocial work environment. Moreover, the associations between personality traits and SBS, and between DCS and SBS, differed between males and females. Over all, the investigated occupants of suspected sick-buildings were within the normal range for both KSP and SOC norms. However, those with symptoms showed prominent personality vulnerability, especially in anxiety, aggressivity, and lower SOC, compared to those that were not reporting symptoms. Female gender, low age, asthma, and a history of atopy were related to SBS in the general working population. A combination of low social support and either passive, strained, or active work situation, as well as a combination of high social support and active work situation, were associated with SBS. In conclusion, measurements of personality and psychosocial work environment could be of value in future studies on environmental syndromes. Moreover, the demans-control-support model can predict SBS, but in a more complex way than indicated by earlier research.

Orientador: Luiz Francisco Malmonge / Resumo: Nanocompósitos com matriz de fibras em escala micro e nanométrica de poli(fluoreto de vinilideno) – PVDF com adição de argila montmorilonita ou zeólita faujasita – FAU, nas concentrações de 3%, 5%, 10%, 20% e 30%, foram produzidas pela técnica de fiação por sopro em solução e submetidas a caracterizações morfológica e estrutural (Microscopia Eletrônica de Varredura – MEV, Difratometria de Raios X – DRX e Energia Dispersiva de Raios X – EDX). As análises térmicas foram feitas por Calorimetria Exploratória Diferencial – DSC e Análise Termogravimétrica – TGA; as mecânicas por análises de Tensão – Deformação; e de molhabilidade por Ângulo de Contato. As amostras foram submetidas a testes de remoção de metais pesados através da adsorção em banho e em membrana. Os resultados demonstraram queda da espessura dos nanocompósitos, que passaram de 500 μm do polímero puro, para 251 μm e 315 μm para os nanocompósitos com 30% de argila e FAU, respectivamente. A técnica de MEV evidenciou amostras com grande quantidade de fibras lisas, uniformes, cilíndricas e pouco aglomeradas, cujos diâmetros foram inferiores a 200 nm. A ferramenta de EDX confirmou a presença dos elementos da argila e da FAU dispersos por todo o filme, porém surgem aglomerados com o aumento de sua concentração. A técnica de DRX demonstrou a presença das fases cristalinas α e β da matriz, além disso, o aumento da quantidade de argila e FAU nos nanocompósitos intensificou seus picos característicos. A técnica DSC revelou que ... (Resumo completo, clicar acesso eletrônico abaixo) / Doutor

Las nuevas tecnologías han implicado un cambio en nuestras conductas dentro de la sociedad, dentro de ello la forma como utilizamos el mercado financiero. Así, actualmente las nuevas figuras como el Dinero Electrónico y Crowdfunding plantean nuevos retos a considerar.Al respecto, en nuestro país tenemos una reciente ley de Dinero Electrónico y la Superintendencia de Banca y Seguros emitió una alerta referida al uso de la figura del Crowdfunding como mecanismo de financiemiento, así el Dr. Morachimo nos explica la naturaleza de las presentes figuras y sus implicancias en nuestra legislación.

Orientador: Prof. Dr. Gerson Luiz Mantovani / Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Nanociências e Materiais Avançados, 2016. / Blendas de poli(acrilonitrila-estireno-butadieno) (ABS) com modificadores de impacto tipo estireno-butadieno-estireno (SBS) foram obtidas para melhorar ainda mais a resistência ao impacto e melhorar a processabilidade de determinados tipos de ABS. Neste trabalho o objetivo foi à obtenção de blendas ABS/SBS e a investigação do comportamento de resistência ao impacto em função da temperatura. As blendas foram obtidas por extrusão de três diferentes tipos de ABS com diferentes conteúdos de SBS. Foram caracterizadas as propriedades de fluxo, as propriedades reológicas, as propriedades mecânicas e a morfologia de fratura dos materiais obtidos. Concluiu-se que não ocorreu a tenacificação do ABS com adição dos conteúdos de SBS, com exceção das blendas ABS 1 com mais de 10% em massa de SBS. Isto mostrou a influência das características e da composição dos ABS e do SBS, e do processamento no comportamento mecânico e na morfologia obtida pela blendas, além da influência do conteúdo em massa de SBS adicionado. As análises das morfologias de fratura mostraram que as blendas de ABS 1 com mais de 10% em massa de SBS possuem um tamanho de partículas menor que nas blendas ABS 2/SBS e ABS 3/SBS, e também uma melhor distribuição das partículas. Nos resultados dos ensaios de tração notou-se um aumento no alongamento na ruptura com o aumento do conteúdo de SBS nas blendas, com uma pequena diminuição do módulo de elasticidade e na tensão no escoamento. Porém, a adição do copolímero em bloco fez com que houvesse uma melhora na processabilidade nas blendas que foi observado nos ensaios de MFI, reometria capilar e reometria de torque. / Blends of poly(acrylonitrile-styrene-butadiene) (ABS) with impact modifiers type styrene-butadiene-styrene (SBS) were obtained to further improve the impact resistance and improving processability of certain types of ABS copolymer. In this work, the objective was to obtain of ABS/SBS polymer blends and the investigating the behavior of the impact resistance versus temperature. The blends were extruded from different types of ABS with different SBS content. Were characterized the flow properties, rheological properties, mechanical properties and fracture morphology of the materials. Concludes that there wasn¿t toughening of ABS with addition of SBS content, except ABS 1/SBS blends with more than 10 w.t% of SBS. This showed the existence dependency characteristics and composition of ABS and processing in the mechanical behavior and morphology of the blends obtained, besides the influence of the content of SBS added. The analysis of fracture morphology showed that blends of ABS 1 copolymer with more than 10 w.t% of SBS having a less particle size than in the ABS 2/SBS blends and ABS 3/SBS blends, and better distribution of the particles. In the results of tensile tests were noted an increase in elongation at break with increasing content of SBS in the blend, with a small decrease in the elastic modulus and yield strength. However, the addition of block copolymer had caused an improvement in processability in the blends, which was observed in the MFI tests, capillary rheometer and torque rheometer.

The objective of this study was to modify the asphalt binder (LA) with 50/70 penetration by incorporating SBS (3, 4 and 4.5%) and the cashew nut shell liquid (CNSL) (1% w/w). The studies were directed towards assessing and analyzing the rheological master curves obtained from tests on a dynamic-shear rheometer (DSR). In addition, we assessed the effects of additives in relation to the viscosity, storage stability, and oxidative aging simulated at the RTFOT. The results indicated that the addition of SBS increases the stiffness and the elastic response of the binder at high temperatures. The master curves showed improvements in the rheological parameters at intermediate and high temperatures, where the process of permanent deformation occurs. Samples with SBS contents 3, 4 and 4.5% were tested for storage stability for 48 hours. The sample with 3% SBS showed no phase separation when stored under the conditions investigated, however, samples with 4 and 4.5% of SBS showed phase separation. In these samples (4 and 4.5%), the addition of CNSL embedded in the modified binder by SBS show the potential to estabilize the binder-polymer mixture, avoiding phase separation. The CNSL, therefore, proved to be potentially useful to prevent phase separation of the LAs with the polymer. The results also indicate that the presence of CNSL promoted a reduction in viscosity and flow activation energy of the binder modified by SBS, contributing thus to improve the thermal susceptibility of the modified binder. Tests of resilient modulus (MR) and tensile strength (RT) in asphalt mixtures containing modified binder suggest that the presence of SBS makes the mixture less susceptible to deformation and failure than mixtures with pure LA. However, the asphalt mixture containing the binder modified by SBS with the addition of CNSL presents an even greater hardening when compared to the SBS blend containing no additive. It is likely that the presence of polymerized CNSL has contributed to the hardening of the sample. / O objetivo deste trabalho foi modificar o ligante asfÃltico (LA) com penetraÃÃo 50/70 pela incorporaÃÃo de SBS (3, 4 e 4,5% m/m) e do lÃquido da castanha do caju (LCC) (1% m/m). Os estudos foram dirigidos para avaliaÃÃo dos parÃmetros reolÃgicos e anÃlise das curvas mestras obtidas atravÃs de ensaios realizados em um reÃmetro de cisalhamento dinÃminco (DSR). AlÃm disso, foram avaliados os efeitos da presenÃa dos aditivos em relaÃÃo à viscosidade, estabilidade à estocagem e envelhecimento oxidativo simulado em estufa RTFOT. Os resultados indicaram que a adiÃÃo de SBS aumenta a rigidez e a resposta elÃstica do ligante em altas temperaturas. As curvas mestras mostraram melhorias nos parÃmetros reolÃgicos em temperaturas intermediÃrias e altas, onde ocorre o processo de deformaÃÃo permanente. As amostras com teores de 3, 4 e 4,5% foram testadas quanto à estabilidade a estocagem por 48h. A amostra com teor de 3% SBS nÃo apresentou separaÃÃo de fases quando estocada nas condiÃÃes trabalhadas, no entanto, as amostras com teores de 4 e 4,5% apresentaram separaÃÃo de fases. Nessas amostras (4 e 4,5%), a adiÃÃo do LCC incorporado ao ligante modificado por SBS demonstrou estabilizar a mistura ligante-polÃmero, evitando a separaÃÃo de fases. O LCC, portanto, mostrou-se potencialmente Ãtil para prevenir a separaÃÃo de fases dos LAs modificados com o polÃmero. Os resultados tambÃm indicam que a presenÃa do LCC promoveu uma reduÃÃo na viscosidade e na energia de ativaÃÃo de fluxo do ligante modificado por SBS, contribuindo, portanto, para melhorar a susceptibilidade tÃrmica do ligante modificado. Os ensaios de mÃdulo de resiliÃncia (MR) e reistÃncia a traÃÃo (RT) nas misturas asfÃlticas contendo os ligantes modificados sugerem que a presenÃa do SBS torna a mistura menos susceptÃvel à deformaÃÃo do que as misturas com o LA puro. No entanto, a mistura asfÃltica contendo o ligante modificado por SBS com adiÃÃo de LCC apresenta um endurecimento ainda maior quando comparada a mistura que contÃm o SBS sem o aditivo. à provÃvel que a presenÃa de LCC polimerizado tenha contribuÃdo para o endurecimento da amostra.

No description available.

No description available.

Esta pesquisa tem como objetivo estudar a relação entre parâmetros de compactação e de deformação permanente à luz dos ensaios de compactação giratória Superpave ® e de ensaios de compressão uniaxial estática e dinâmica. Foram estudadas 8 misturas asfálticas com a mesma granulometria (Faixa C) e tipo de agregado mineral (granito) porém variou-se o ligante asfáltico (CAP 50/70 e CAP 50/70+SBS), o volume de vazios (4% e 7%) e a adição de cal hidratada. A partir dos resultados do ensaio de compactação observou-se que a inclinação das curvas de compactação das misturas compactadas a 7% foram mais acentuadas do que as de 4% e os parâmetros incidentais deste ensaio foram sensíveis à presença de cal e à variação do asfalto das misturas testadas. Quanto aos resultados dos ensaios de creep estático e dinâmico, notou-se que as misturas com Vv de 4% e as com asfalto modificado apresentam menor suscetibilidade à deformação permanente, no entanto, essas vantagens do asfalto modificado foram observadas somente nos ensaios de creep dinâmico. No que se refere às relações entre os parâmetros de compactação e de deformação permanente, os ajuste não se mostraram promissores como verificado pela qualidade dos ajustes (R2) exceto para algumas relações com CDI e TDIm. / This research aims to study relations between compaction and permanent deformation by means of Superpave® gyratory compaction and static and dynamic creep tests. Thus, eight asphalt mixtures were evaluated which were composed by same type (granite) and gradation (dense) of mineral aggregate but two types of asphalt binder (Pen 50/70 AC and Pen 50/70+SBS AC), two different levels of air voids (4% and 7%) and the addition of hydrated lime. Compaction results indicated that curve slopes of 7% air void asphalt mixtures were stronger than the 4% ones, and compaction parameters were sensitive to lime addition and asphalt type change. Static and dynamic creep test results indicated that 4% air void and modified asphalt mixtures presented lower susceptibility to rutting, but, these modified asphalt advantages were observed only in dynamic creep tests. In regard to relation between compaction and rutting parameters, linear models did not fit accurately, excepting some CDI and TDIm ones.

O copolímero SBS é o aditivo mais empregado mundialmente na modificação de ligantes asfálticos, por melhorar diversas de suas características. Um dos principais problemas deste tipo de formulação é a separação de fases, que pode ser minimizada com a incorporação de aditivos. Um novo polietileno de alta densidade e baixo peso molecular oxidado (com denominação comercial TITAN 9686) foi utilizado nesta pesquisa, com o objetivo de testar a hipótese de que a adição de proporções adequadas deste aditivo possa melhorar as características reológicas do asfalto+SBS. O experimento laboratorial foi delineado com base na técnica de experimentos com misturas, englobando um total de nove formulações compostas com asfalto, SBS e TITAN. O teor de SBS variou entre 0 e 5% em peso e o de polietileno variou entre 0 e 2% em peso. Foi utilizado óleo aromático no teor de 4% em peso para todas as nove misturas. As misturas foram analisadas em três condições de envelhecimento: virgem, curto prazo (na estufa RTFO) e longo prazo (na estufa PAV). Foram realizados os seguintes ensaios reológicos: (i) de cisalhamento em regime oscilatório em diferentes condições de temperatura e frequência (para medida do módulo complexo e do ângulo de fase, usados na determinação do grau de desempenho, no cálculo dos parâmetros G*/sen(δ) e G*.sen(δ) e na construção de curvas-mestre), (ii) de viscosidade Brookfield, (iii) de fluência e recuperação sob múltiplas tensões (para medida do percentual de recuperação e da compliância não-recuperável), (iv) de varredura de amplitude linear (para cálculo do parâmetro a f e para ajuste do modelo de fadiga) e (v) de estabilidade à estocagem. Acerca das características escolhidas para mensurar a melhora ou piora das propriedades das misturas asfalto+SBS com a adição de TITAN, podem ser feitas as seguintes observações: (i) a estabilidade à estocagem é melhorada com a adição de TITAN, em particular no teores entre 1 e 2%; (ii) a sensibilidade ao envelhecimento tanto a curto quanto a longo prazos diminui com a adição de TITAN; (iii) a adição de TITAN aumenta a resistência à deformação permanente, à luz dos parâmetros Jnr e R e aumenta a sensibilidade dos ligantes asfálticos modificados com SBS a mudanças bruscas nos níveis de tensão aplicados; e (iv) a adição de TITAN contribui com o aumento da resistência à fadiga, à luz dos parâmetros Nf , a baixos níveis de deformação, e af , e a prejudica reduzindo o parâmetro Nf a altos níveis de deformação e aumentando a temperatura crítica de fadiga ou o parâmetro G*.sen(δ). Tendo por base estas evidências, é possível concluir que a adição de TITAN, em linhas gerais, melhorou a estabilidade dos ligantes asfálticos modificados com até 5,0% de SBS. Com base nas análises realizadas, é possível afirmar que teores da ordem de 1 a 2% de TITAN, para teores de SBS entre 3,0 e 5,0%, são recomendáveis, à luz das propriedades, índices e parâmetros analisados neste trabalho. / The SBS copolymer is the most widely used additive in asphalt binder modification, since it enhances many of the properties of the original material. A critical problem that arises from this type of modification is phase separation, which can be minimized by adding other modifiers to the formulation. A new oxidized, high-density polyethylene with low molecular weight (commercial designation of \"TITAN 9686\") was used in the study with the purpose of verifying the hypothesis that the addition of suitable contents of this modifier can improve the rheological properties of the SBS-modified binder. The laboratory matrix of formulations was based on the experiments with mixtures, and nine types of materials were prepared with asphalt binder, SBS and TITAN. The SBS contents ranged from 0 to 5% by weight, whereas the polyethylene contents ranged from 0 to 2% by weight. These formulations also contained 4% of aromatic oil by weight. Three aging conditions were selected: unaged, short-term aged in the rolling thin-film oven (RTFO) and long-term aged in the pressurized aging vessel (PAV). The following tests were carried out: (i) dynamic oscillatory shear at different temperatures and frequencies of loading for the determination of the complex modulus, the phase angles and the master curves, as well as the performance grades and the numerical values of the parameters G*/sin(δ) and G*.sen(δ); (ii) rotational viscosity; (iii) creep and recovery at multiple stress levels for the determination and the percent recovery and the nonrecoverable compliance; (iv) linear amplitude sweep, in order to calculate the parameter a f and fit the fatigue model to the data; and (v) storage stability. With respect to the characteristics used in the evaluation of the properties of the AC+SBS mixtures after the addition of TITAN, the following observations can be made: (i) storage stability is improved when TITAN is added to the formulation, especially at contents ranging from 1 to 2%; (ii) the sensitivity to the short-term and long-term aging processes decreased with the incorporation of TITAN; (iii) the changes in the R and the Jnr values indicate that the addition of TITAN makes the asphalt binder more resistant to rutting, and also increases the sensitivity of the SBS-modified binders to sudden increases in the stress level; and (iv) the presence of TITAN in the material leads to an increase in the fatigue resistance as based on the parameters Nf and af at low strain levels and the increases in the critical fatigue temperature and the parameter G*.sen(δ). With reference to these evidences, it is possible to conclude that the addition of TITAN generally improves the storage stability of the SBS-modified binders with no more than 5% of copolymer by weight. Based on the results of the present study, it is possible to say that percentages between 1 and 2% of TITAN by weight are recommended for SBS contents between 3 and 5% by weight.