O objetivo do presente trabalho foi avaliar o desempenho de um reator de leito fixo e fluxo ascendente (RLFFA) em escala de bancada submetido à baixa aeração e recirculação. O reator foi utilizado como um sistema de pós-tratamento do efluente de indústria de fabricação de ração animal (INCOFAP) a partir de resíduos de abatedouro de aves, caracterizado por elevada carga de nitrogênio amoniacal. Para tanto, o RLFFA foi avaliado quanto à remoção da fração remanescente de matéria orgânica e de nitrogênio do efluente do reator UASB instalado na indústria. O RLFFA foi operado em condições mesofílicas (30°C) e tinha volume total de 11,5 L e volume útil de 6,1 L, com leito estruturado composto por 13 estruturas cilíndricas (3 cm de diâmetro) de espuma de poliuretano, dispostas verticalmente no interior do reator. O reator apresentou sistema de recirculação interna, com razão de recirculação igual a 3, suficiente para garantir a mistura completa. O sistema foi operado em três condições distintas, que foram denominadas de fases, todas com tempo de detenção hidráulica (TDH) de 24 horas e concentração de oxigênio dissolvido próxima a 1,0 mg.L-1. Nas fases 1 e 2, o RLFFA foi alimentado com 20% de efluente do UASB diluídos em água, e a alimentação da Fase 3 foi com 10% de efluente. As relações DQO/N para as Fases de 1 a 3 foram de, respectivamente, 0,28, 0,41 e 0,26. Na Fase 1, a alcalinidade foi mantida em concentração estequiométrica para a ocorrência da nitrificação total, enquanto nas fases 2 e 3 a alcalinidade foi adicionada em excesso. As melhores eficiências de remoção de N-total e DQO foram obtidas na Fase 1, com respectivamente, 48 ± 24% e 63 ± 20%, atingindo remoção máxima de N-total de 79% e 92% para DQO. As análises estatísticas demonstraram independência entre a remoção de DQO e a remoção de N-total, e com demanda de doador de elétrons para desnitrificação heterotrófica via nitrato superior à DQO removida, indicando a ocorrência de vias complementares. A desnitrificação via nitrito e a desnitrificação autotrófica foram observadas nos ensaios cinéticos de desnitrificação via nitrito e teste de atividade para desnitrificação autotrófica utilizando sulfeto como doador de elétrons. A modelagem para qualidade da água do rio Chibarro( local de lançamento do efluente da empresa INCOFAP) utilizando uma modificação do modelo de Streeter-Phelps, indicou que o cenário com a adoção do reator estudado no presente trabalho para tratamento do efluente da INCOFAP permitiu reduzir o impacto para a qualidade da água do rio Chibarro ao se comparar ao sistema atual de tratamento do efluente da empresa INCOFAP. Entretando, ainda faz-se necessária a elevação da eficiência de remoção de N-total no sistema, para atingir a concentração máxima de N-amoniacal permitida de 20 mg.L-1 para o efluente para compatibilização com a capacidade de autodepuração do rio Chibarro. / The objective of this study was to evaluate the performance of a bench scale up-flow fixedbed reactor (UFBR) subjected to low aeration and effluent recirculation.The reactor was used as a post-treatment system of effluent from animal food plant (INCOFAP) using poultry slaughterhouse wastes, characterized by high ammoniacal nitrogen load rate.Therefore, the UFBR was evaluated in respect to residual organic matter and nitrogen removal of industrys UASB reactor effluent. The UFBR was operated in mesophilic conditions (30°C) and it had a total volume of 11.5 L and a working volume of 6.1 L, with a structured bed composed by 13 polyurethane foam vertical cylindrical structures (3 cm of diameter) inside the reactor. The reactor was provided with internal recirculation system with recirculation ratio of 3, suficiente to guarantee a complete mixture. The system was operated in three different phases, with hydraulic retention time (HRT)of 24 hours and dissolved oxygen concentration close to 1.0 mg.L-1.On Phases 1 and 2, the UFBR was fed with 20% of UASB effluent diluted in water,and the Phase 3 was fed with 10% of effluent. On phases 1 to 3 COD/N ratios were, respectively, 0.28, 0.41 and 0.26. The alkalinity on Phase 1 was maintained on stoichiometric concentration to total nitrification, while in phases 2 and 3 excess alkalinity was added. The best total nitrogen and COD removal efficiencies were obtained in Phase 1, with respectively, 48 ± 24% and 63 ± 20% , reaching maximum total nitrogen removal of 79% and 92% for COD. Statistical analysis demonstrated independency between COD and total nitrogen removal, and with higher electron donor demand for nitrate denitrification than COD removal, indicating the occurrence of complementary paths. The nitrite denitrification and autotrophic denitrification were noted in kinetics experiments and activity tests for autotrophic denitrification using sulfide as source of electron donors. The modeling for Chibarro river water quality (site of INCOFAPs effluent release) , using a modified Streeter-Phelps model, indicated the scenario with the adoption of the studied reactor on this work for INCOFAP's effluent treatment provided the reduction of the impact on Chibarros water quality in comparison with the current effluent treatment of INCOFAP. However, it is still necessary an increase on system denitrification efficiency to reach the maximum ammoniacal nitrogen concentration allowed of 20 mg.L-1 for the effluent to make compatible with de selfpurification of Chibarro river.

Utilizou-se reator de leito estruturado e aeração intermitente (RLEAI) como pós-tratamento de efluentes de reator UASB tratando esgoto sanitário. O volume total e o tempo de detenção hidráulica (TDH) do reator UASB eram de 11,2 L e 9 horas, respectivamente. O RLEAI possuía volume total de 11,0 L e, devido às hastes cilíndricas verticais de espuma de poliuretano usadas como suporte para a biomassa, o volume útil foi de 9,6 L. Este reator foi operado com um TDH de 12 horas, razão de recirculação igual a 3 e foi alimentado continuamente com efluente do reator UASB. O objetivo deste trabalho foi avaliar a influência do tempo de aeração no desempenho do RLEAI na remoção de matéria orgânica e nitrogênio. O reator foi operado com aeração contínua, e tempos de aeração intermitentes (tempo aerado/não aerado) de 2h/1h, 1h/1h, 0,75h/1,25h, 1h/ h e 1h/3h. Em todas as fases a DQO efluente ao sistema ficou entre 26 e 42 mg.L-1. A fase de aeração contínua foi fundamental para o estabelecimento da comunidade nitrificante no sistema. A oxidação do nitrogênio total (como NTK) para nitrato aumentou de 62% (aeração contínua ) para 82% (aeração intermitente de 1h/2h) devido à alcalinidade gerada pela desnitrificação, estimulada pelo período não aerado. Na fase 1h/3h a oxidação do NTK foi prejudicada pela falta de oxigênio, e a eficiência nesta fase foi de 42%. A maior remoção estável de N-total foi obtida na fase 1h/2h com eficiência de 29%. Foi observado no ensaio em batelada que a velocidade de desnitrificação via nitrato aumentou de 0,90 mg N. g SSV-1.h-1 para 2,55 mg N. g SSV-1.h-1 após aclimatação da biomassa em condições de excesso de matéria orgânica. Concluiu-se que a remoção de N-total foi limitada pela baixa quantidade de matéria orgânica advinda do reator UASB, sendo a relação DQO/N do afluente ao RLEAI de 3,04. A elevada oxidação de NTK e de remoção de matéria orgânica, aliadas à baixa produção sólidos e ao alto tempo de retenção celular (139 dias), mostram que o RLEAI é uma alternativa interessante em comparação às tecnologias praticadas atualmente para pós tratamento de efluentes de reatores anaeróbios. / This study used a structured bed reactor under intermittent aeration for post-treatment of UASB rector treating domestic sewage. The UASB reactor had a total volume of 11.2 L and 9 hours of hydraulic retention time (HRT). The structured bed reactor had a total volume of 11.0 L and working volume of 9.6 L due to the vertical cylindrical rods with polyurethane foam used as a support for the biomass. This reactor was operated whit 12 hours of HRT, recirculation ratio equal to 3 and was continuously fed with effluent from the UASB reactor. The aim of this study was to evaluate the influence of aeration time on RLEAI performance in removal of organic matter and nitrogen. For this the reactor was operated with continuous aeration and intermittent aeration periods (time aerated/ non-aerated) of 2h/1h, 1h/1h, 0.75h/1.25h, 1h/2h e 1h/3h. During all operation time the COD effluent to the system it was between 26 and 42 26 e 42 mg.L-1. The continuous aeration operation was fundamental to the establishment of the nitrifying microorganism community in the system. The TKN oxidation to nitrate increase from 62% (continues aeration) to 82% (intermittent aeration 1h/2h) due to the alkalinity generated by denitrification, that was stimulated by non-aerated period. In the intermittent aeration period of 1h/3h the NTK oxidation was damaged by a lack of oxygen; the efficiency at this stage was 42%. The most stable total nitrogen removal was obtained in 1h/2h aeration period with 29% efficiency. It was observed in the batch test that nitrate denitrification rate increased from 0.90 mg N. g VSS-1.h-1 to 2.55 mg N. g VSS-1.h-1 after acclimation of biomass in conditions of excess organic matter. It was inferred that the removal of total nitrogen was limited by the low amount of organic matter load from the UASB reactor; the COD/N ratio of the influent was 3.04. The high NTK oxidation and high organic matter removal, combined with low solid production and high cell retention time (139 days), leads to the conclusion that the structured bed reactor under intermittent aeration is an interesting alternative compared to the technologies currently applied for post treatment of anaerobic reactors effluent.

Submitted by Geandra Rodrigues (geandrar@gmail.com) on 2018-06-12T15:22:34Z No. of bitstreams: 1 marianabarbosaleitesergioferreira.pdf: 4566422 bytes, checksum: 501376413029df1acba985140f748de1 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2018-06-14T11:33:27Z (GMT) No. of bitstreams: 1 marianabarbosaleitesergioferreira.pdf: 4566422 bytes, checksum: 501376413029df1acba985140f748de1 (MD5) / Made available in DSpace on 2018-06-14T11:33:27Z (GMT). No. of bitstreams: 1 marianabarbosaleitesergioferreira.pdf: 4566422 bytes, checksum: 501376413029df1acba985140f748de1 (MD5) Previous issue date: 2018-02-28 / No pós-tratamento do câncer de mama compreendido como o término da quimioterapia e/ou radioterapia e a intervenção cirúrgica, as mulheres ainda lidam com diversos estressores que podem repercutir fortemente em sua saúde mental. Dessa forma, considerando-se que as mulheres adotam estratégias de enfrentamento (coping) para lidar com tais estressores, o presente estudo tem como objetivo identificar as estratégias de enfrentamento utilizadas pelas pacientes e sua relação com o nível de resiliência e otimismo - aspectos que são considerados saudáveis para o desenvolvimento humano. Para isso, a pesquisa tem uma abordagem quantitativa e qualitativa e, adotou-se uma entrevista para compreender as repercussões negativas e positivas do câncer de mama para a vida atual da mulher, a Escala de Resiliência desenvolvida por Wagnild e Young, a Escala Modos de Enfrentamento de Problemas (EMEP) e o Revised Life Orientation Test (LOT-R) de Scheier, Carver e Bridges, este último como escopo para a avaliação do otimismo. A amostra foi constituída por 50 mulheres que estavam no pós-tratamento do câncer, com idade entre 32 a 75 anos de idade (M= 54, 52; DP= 8, 75) e, como resultado, constatamos que não houve associação significativa entre as estratégias de enfrentamento utilizadas com o nível de resiliência e otimismo (p < 0, 05%). Verificamos que a única associação significativa foi entre as variáveis resiliência e otimismo. Apesar de não haver relação significativa entre as variáveis resiliência, estratégias de enfrentamento e otimismo, é possível constatar que a maioria das mulheres pesquisadas utilizou a estratégia de enfrentamento focada no problema (60%), apresentando um moderado índice de resiliência (58%) e um alto índice de otimismo (60%), aspectos que podem estar associados a um bom ajustamento. No mais, constatamos que apesar das mulheres terem relatado consequências negativas relacionadas ao câncer de mama, como por exemplo, dores, prejuízos na vida laboral, medo da recidiva e mudanças nos relacionamentos interpessoais, a maioria apontou efeitos positivos advindos da doença, tais como desenvolvimento de forças pessoais, melhor apreciação da vida e melhoria nas relações interpessoais. Os resultados do presente estudo reforçam a importância de pesquisas que visem compreender o momento do pós-tratamento contra o câncer de mama, como também, estudos que busquem compreender a relação entre variáveis psicológicas capazes de favorecer o ajustamento das mulheres que terminaram o tratamento inicial para o câncer de mama. / In the breast cancer post-treatment, understood as the end of chemotherapy and/or radiotherapy, and surgical intervention, women still deal with diverse stressors which might strongly reverberate in their mental health. Thus, taking into consideration that women adopt coping strategies to manage such stressors, the present study aims at identifying the coping strategies used by patients and their relation with the level of resilience and optimism – aspects which are considered healthy for human development. For this purpose, the current research has both a quantitative and a qualitative approach, and an interview was taken in order to understand the negative and positive repercussions of breast cancer for the contemporary life of women, the Resilience Scale developed by Wagnild and Young, the Ways of Coping Scale (WOCS) and the Revised Life Orientation Test (LOT-R) by Scheier, Carver and Bridges, the latter as the scope for optimism evaluation. The sample was made up with 50 women who were in the post-treatment cancer, with the age varying from 32 to 75 (A=54, 53; SD=8,75) and, as a result, it was verified that there was no meaningful association between the coping strategies used with the level of resilence and optimism (p<0,05%). We noticed that the only significant association was between the resilence and optimism variables. Despite the absence of expressive correspondence among the resilience variables, coping strategies and optimism, it is possible to see that most women who participated in the research took advantage of coping strategy focused on the problem (60%), showing a moderate resilience level (58%) and a high level of optimism (60%), aspects which might be connected to a good adjustment. In addition, we observed that in spite of having reported negative consequences related to breast cancer as, for example, pain, loss in the working life, fear of relapse and changes in personal relationships, most women mentioned positive effects that came from the disease such as the development of personal strength, better appreciation of life and improvement in personal relationships. The results of the current study reinforce the importance of research which aims at understanding the moment of breast cancer post-treatment, as well as the studies which try to understand the bond among psychological variables capable of favoring the adjustment of women who have finished the initial treatment for breast cancer.

The human immunodeficiency virus (HIV) epidemic is far from over. Antiretroviral therapy (ART) is effective at suppressing viral replication within a patient but it must be taken daily and is life-long. Therefore, the development of a therapy that could induce drug-free remission or constitute a functional cure is a key focus of HIV research. In this thesis I explore three mechanisms which could lead to more individuals being able to control their viraemia in the absence of ART: (1) T-cell immunity, (2) early initiation of ART, and (3) viral evolution. Firstly, a strong HIV-specific T-cell response has been linked to rare cases of spontaneous viral control, but the extent to which this arm of the immune response contributes to viral control is debated. Several types of data are used to answer this question, including the rate at which the virus evolves to escape the CD8+ T-cell response. I study the frequency of incident immune escape in the largest cohort used for this purpose to date. Secondly, some patients, with characteristics dissimilar to spontaneous HIV controllers, are able to control the virus for years after the interruption of ART that was initiated early in infection. I use mathematical models to investigate a new hypothesis for the differing outcomes of early- and late- initiated ART. Thirdly, since HIV is a relatively new infection of humans it is still adapting to its new host. Recent studies suggest that the virus could be evolving towards decreased virulence at the population level. I study whether the widespread administration of ART has the potential to alter the course of virulence evolution and might result in a further attenuated virus. I conclude by discussing the implications of these results for viral control at the individual level and also for population level epidemic control.

Les couches de conversion actuellement utilisées dans l'industrie aéronautique, pour protéger le métal de la corrosion et favoriser l'adhérence de la peinture, contiennent du chrome hexavalent, composé toxique et cancérigène dont l'utilisation va prochainement être interdite par la réglementation européenne REACh. L'une des pistes envisagée pour remplacer ces couches chromatées est l'utilisation de couches de conversion TCP (Trivalent Chromium Protection). Ces travaux portent sur l'étude des couches de TCP et s'attachent à caractériser chaque étape du traitement de surface industriel, incluant les étapes de prétraitement et de post-traitement. Des techniques d'analyse de surface (XPS, ToF-SIMS, AFM, MEB et PM-IRRAS) ont été utilisées pour analyser la composition chimique et la morphologie de la surface après chaque étape du traitement. Cette étude a été réalisée sur un alliage d'aluminium AA 2024-T3, très utilisé en aéronautique pour ses propriétés mécanique, mais présentant une faible résistance à la corrosion. Les résultats obtenus ont notamment mis en évidence que la couche de TCP se forme sur toute la surface de l'alliage (composés intermétalliques et cavités), et ont permis de comprendre comment le post-traitement permet d'améliorer la résistance à la corrosion de la couche de TCP. Ces travaux s'intéressent également à des couches de conversion sans chrome, à base de zirconium, étudiées ici pour servir de point de départ au développement d'une conversion sans chrome qui respecterait les exigences de résistance à la corrosion. / Conversion coatings are used in aerospace industry to protect the metal from corrosion and to promote paint adhesion. Currently, chromate conversion coatings are used, but chromate is toxic and carcinogenic and its use will be forbidden by the European REACh regulation. TCP (Trivalent Chromium Protection) conversion coatings, are considered as a promising alternative to replace chromate conversion coating. This work focuses on the characterisation of the TCP layer and considers each step of the industrial surface treatment, including pre-treatment and post-treatment steps. Surface analytical techniques (XPS, ToF-SIMS, AFM, SEM and PM-IRRAS) were used to analyse the chemical composition and morphology of the surface after each step in the process. This work was done on an aluminium alloy AA 2024-T3, commonly used in the aerospace industry for its good mechanical properties, but poorly resistant to corrosion. The results obtained demonstrate, among other things, that the TCP layer totally covers the surface (intermetallic compounds and cavities) and enable to understand how the post-treatment can improve the corrosion resistance of the TCP coating. This work also focuses on conversion coating based on zirconium, which are studied here to be used as a starting point to develop a new conversion coating without chromium, meeting the corrosion resistance requirement.

The aim of the study is to determine the nature and utilisation of an Employee Assistance Programme (EAP) in a white-collar work environment, and, more specifically, in a South African context. Information about the research topic was obtained from accumulate records of the Standard Bank's Employee Well-being Programme (EWP), structured interviews which were conducted with eleven EWP practitioners and a union representative, and from self-administered questionnaires which were completed by a sample of 153 of the bank's employees. The study includes an in-depth literature review on EAPs in general and issues such as the nature and scope of the bank's EWP, the extent to which the EWP addresses employees' needs, the nature and extent of the marketing of the EWP, and the extent to which the workforce is utilising the programme, were explored and described. The main findings are that the EWP shows evidence of acceptance by employees as well as a degree of utilisation that compares favourably with local and international trends. It also shows an incongruence between marketing and employee orientation and training initiatives and reveals that programme evaluation efforts are insufficient and could be significantly improved. Accordingly, recommendations have been made pertaining to the needs of employees, employee and union involvement, a multi-disciplinary approach to case management, marketing, training and evaluation with regard to the EWP, an EWP database, and a post-treatment follow-up. / Social Work / M.A. (Social Work)

O presente trabalho teve como objetivo principal a avaliação da eficiência de remoção de carga orgânica, fósforo e sólidos em suspensão de sistema de flotação tratando esgoto sanitário pré-tratado em reatores UASB, da ETE Monjolinho da cidade de São Carlos/SP, e coagulado com tanino associado ou não a polímeros sintéticos. Os ensaios com variação de dosagem de coagulante Tanino e polímeros (polímero catiônico, polímero não-iônico e polímero aniônico) foram realizados em escala de laboratório, com o uso do equipamento flotateste. Em todos os ensaios foram fixados os valores de gradiente de velocidade na mistura rápida (800/s) e na floculação (90/s), ao tempos de detenção na mistura rápida (20 s) e na floculação (15 min) e, a pressão de saturação 5 Bar e a razão de recirculação (17%). Durante os ensaios com unidade de flotação em escala de bancada foram avaliados três valores de velocidades de flotação: 12,0 cm/min, 16,0 cm/min e 20,0 cm/min. Os ensaios foram divididos em duas fases: a fase 1 teve como objetivo analisar a resposta do sistema de flotação com o emprego do coagulante Tanino no tratamento do efluente do reator UASB da ETE Monjolinho (fase 1A) e também determinar as duas dosagens do coagulante Tanino mais adequadas para o tratamento do efluente de UASB da ETE Monjolinho para cada polímero testado (fase 1B). As fases 1A e 1B foram realizadas com efluente coletado às 8:00 h e 14:00 h, respectivamente. A fase 2 teve como objetivo a busca da dosagem ótima de tanino dentro de uma faixa mais estreita de valores, assim como a verificação do melhor tipo e dosagem de polímero sintético (não-iônico, aniônico e catiônico) para ser associado ao coagulante tanino. Na fase 1A, verificou-se que a flotação foi efetiva para remoção de cor aparente mesmo para dosagem nula de coagulante Tanino. Quanto à turbidez, verificou-se efeito marcante da adição de dosagem crescente de coagulante no aumento da eficiência de remoção desse parâmetro. Após a obtenção dos resultados da fase 1B, foram escolhidas para a fase 2 as duas menores dosagens de coagulante capazes de promover redução da turbidez em pelo menos 85%. Além destas duas dosagens, foram avaliados na fase 2 outras 3 dosagens compreendidas entre elas. Sendo assim, na fase 2 foram estudadas as doses de 65, 75, 85, 95 e 105 mg/L de coagulante, cada qual associada a seis dosagens de cada um dos polímeros estudados. Entre os tratamentos empregados, pôde-se verificar maior eficácia do polímero não-iônico e do polímero catiônico para o tratamento por flotação, associado ao coagulante tanino. O conjunto de dosagem de coagulante tanino e polímero mais vantajoso, ou seja, menor dosagem de tanino que, associada a polímero, apresentou remoção satisfatória dos parâmetros estudados, foi 65 mg/L de Tanino e 2,0 mg/L de polímero catiônico, atingindo remoções de 95,2% de turbidez (Residual de 3,65 NTU), 82,1% de cor aparente (Residual de 98 mgPT/L), 49,2% de fósforo total (Residual de 3,2 mg/L), 80,7% de DQO (Residual de 25 mg/L) e 87,9 % de SST (Residual de 13 mg/L) nas condições encontradas na época dos ensaios, para o pós-tratamento por flotação de efluente de reator UASB da ETE Monjolinho, São Carlos/SP. / The main objective of this work is the evaluation of the efficiency of removal of organic load, phosphorus and suspended solids in the flotation system treating domestic wastewater pretreated in UASB reactors, of the Monjolinho Wastewater Treatment Plant (WWTP) of Sao Carlos, SP and clotted with tannin alone or combined with synthetic polymers. Tests varying tannin dosage of coagulant and polymer (cationic polymer, nonionic polymer and anionic polymer) were performed on a batch scale, using flotatest. In all the tests were fixed the values of rapid mix (800/s) and flocculation (90/s) velocity gradients, the rapid mix (20 s) and flocculation (15 min) times, saturation pressure (5 Bar) and recycle rate (17%). During the test in the flotation bench scale unity three values of flotation velocities were evaluated: 12.0 cm/min, 16.0 cm/min and 20.0 cm/min. The tests were divided in two phases: the objective of phase 1 was to examine the response of the flotation system with the use of tannin coagulant in the treatment of Monjolinho WWTP UASB effluent (Phase 1A) and also determine the two most suitable dosages of tannin coagulant for the treatment of wastewater from the Monjolinho WWTP UASB tested for each polymer (phase 1B). Phases 1A and 1B were performed with wastewater collected at 8:00 h and 14:00 h, respectively. The objective of phase 2 was to find the optimum dosage of tannin within a narrower range of values, as well as verification of the optimal type and dosage of synthetic polymer (non-ionic, anionic and cationic) to be associated with the tannin coagulant. In phase 1A, it was found that flotation was effective for apparent color removal even to zero coagulant dosage tannin. As for turbidity, there is a marked effect when increasing the coagulant dose, which increased the removal efficiency of this parameter. After obtaining the results of Phase 1B, were chosen for phase 2 two low coagulant dosages which can promote reduction of turbidity by 85%. Besides the two dosages obtained in phase 1B, in phase 2 were evaluated other three between them. Thus, in phase 2 were studied coagulant doses of 65, 75, 85, 95 and 105 mg/L, each one associated with six doses of each one of the studied polymers. Among the treatments employed, it could be seen that the non-ionic polymer and the cationic polymer were the most efficient for treatment by coagulation associated with tannin in flotation. The set of tannin coagulant dosage and polymer which showed satisfactory removal of parameters was 65 mg/L of Tannin with 2.0 mg/L of cationic polymer, reaching 95.2% removal of turbidity, 83% of color apparent, 49.2% of total phosphorus, COD 80.7% and 87.9% of TSS under the conditions found at the time of testing, for post-treatment of Monjolinho WWTP UASB effluent by flotation.

Nas últimas décadas diversos tipos de meio suporte têm sido propostos para a melhoria da eficiência e/ou aumento da compacidade de reatores biológicos tratando esgoto sanitário. No presente trabalho de doutorado são apresentados os resultados obtidos com a aplicação de um novo tipo de reator biológico anaeróbio de fluxo ascendente com leito de fibras flexíveis aplicado ao tratamento de esgoto sintético. Sua concepção foi motivada pelas dificuldades verificadas em alguns tipos de reatores de leito expandido, os quais ao longo do tempo de operação podem perder suas características hidrodinâmicas iniciais, devido ao acúmulo de biomassa, passando a apresentar expansão não homogênea do leito. A proposta de uso da fibra de nylon como meio suporte se deveu a sua capacidade de atuar como leito flexível - quando fixo em apenas uma de suas extremidades - que, devido á sua flexibilidade, apresenta também características parecidas às de leito móvel. Nesse novo tipo de concepção de leito, a biomassa aderida às fibras flexíveis adquirem forma de longos filamentos, os quais, devido ao próprio escoamento do esgoto e à rotação do eixo em que as fibras são fixadas, permanecem estendidos de modo a proporcionar elevada relação volume/superfície. Essa biomassa na forma de finos filamentos permanece firmemente aderida ás fibras flexíveis, reduzindo o potencial de perda de biomassa juntamente com o efluente e também de possíveis obstruções de poros, comum em leitos granulares. Para o estudo, foi projetada, construída, operada e avaliada durante 458 dias, uma instalação piloto constituída de seis reatores na forma de colunas verticais com escoamento contínuo e ascendente, operando em paralelo. Nesses reatores foram variados parâmetros de configuração e operação, como: i) a densidade de fibras flexíveis que compuseram o leito de fibras flexíveis; ii) a rotação do eixo vertical onde foram fixadas as fibras do leito; iii) o tempo de detenção hidráulica (nas etapas de 1 a 4 foram testados TDH de 9; 6; 4 e 3 horas, respectivamente); iv) a interrupção da rotação em reator em andamento. Foram analisadas as eficiências de remoção de carga orgânica e do perfil vertical dos reatores, assim como foi realizada a avaliação da composição da biomassa encontrada no biofilme, com análise de imagem e microscopia. Os resultados demonstram que a configuração dos reatores forneceram excelentes resultados de remoção de carga orgânica e também se mostraram aptos para se adaptar as variações de vazões aplicadas ao longo do trabalho, sendo observados os melhores resultados na Etapa 1 da fase 1, onde o Reator 2 apresentou eficiência de remoção de 91% de DQO total, 96% de DQO filtrada, 86% de DBO e 60% de SST. Também foi possível observar que os reatores com maiores densidades de fibras apresentaram melhores eficiências e permaneceram mais estáveis em face às características investigadas. Quanto à aplicação de rotação foi possível observar sua interferência positiva sobre a eficiência de remoção dos reatores, principalmente para as densidades de fibras inferiores e que o aumento de sua rotação também trazia melhorias na remoção de carga orgânica. Já para a avaliação da interrupção da rotação foi possível observar a redução de eficiência para os parâmetros avaliados. Também foram analisados três pós-tratamentos do efluente do reator anaeróbio por flotação, sedimentação (com e sem coagulante) e filtração em filtro de fibras flexíveis. O pós-tratamento mais adequado para ser aplicado em conjunto ao reator anaeróbio de fibras flexíveis foi a flotação, por separação (sem adição de coagulante), que apresentou remoção de 71%de turbidez, 51% de cor aparente, 40% de DQO, 25% de DQO filtrada, 34% de fósforo total e 52% de SST. Na avaliação do pós-tratamentos físico-químico mais adequado, a flotação por ar dissolvido apresentou melhores resultados utilizando o coagulante PAC em dosagem de 14 mg.L-1 do princípio ativo de Al2O3, com eficiência de remoção do sistema de 84% de turbidez, 73% de cor aparente, 50% de DQO total e 31% de DQO filtrada, 45% de fosforo total e 62% SST. / In the last decades, many different types of support media have been proposed for improving the efficiency and / or increasing the compactness of biological reactors treating domestic sewage. The results obtained in the application of a new type of up flow anaerobic bioreactor with flexible fibers bed applied to synthetic wastewater treatment are presented in this PhD thesis. Its design was motivated by the difficulties observed in some types of expanded bed reactors, which may lose their initial hydrodynamic characteristics during operation time, due to the biomass accumulation, leading to inhomogeneous bed expansion. The proposed nylon fiber is used as the support media due to its ability to operate as flexible bed - when it is fixed at only one end - which, due to its flexibility, also has characteristics similar to the moving bed. In this new type of bed design, the biomass attached to the flexible fibers acquire the form of long filaments, which, due to the sewage flow and the rotation axis in which the fibers are fixed, remain extended in order to provide high volume /surface ratio. This biomass in the form of fine filament remains firmly attached to the flexible fibers, thereby reducing the potential loss of biomass along with the effluent, as well as possible pore clogging, which are common in granular beds. For this study, a pilot installation consisted of six parallel reactors in the form of vertical columns with continuous upflow was designed, constructed, operated and evaluated for 458 days. In these reactors were varied configuration settings and operation as: i) the density of flexible fibers that composed the bed of flexible fibers; ii) the rotation of the vertical axis where the bed fibers were fixed; iii) the hydraulic retention time (in steps 1 to 4, HDTs of 9, 6, 4 and 3 hours were tested, respectively); iv) interruption of the rotation in the reactor in progress. The organic load removal and the reactors vertical profile efficiencies were analyzed, as well as the biomass composition found in biofilm, with image analysis and microscopy. The results demonstrate that the configuration of reactors provided excellent results of organic load removal and also proved to be able to adapt to variations in flow rates applied during the tests. The best results were observed in Step 1 in phase 1, where the reactor 2 presented removal efficiency of 91% of total COD, 96% of filtered COD, 86% of BOD and 60% of SST. Reactors with higher fiber density presented improved efficiencies and remained more stable, considering the investigated characteristics. The application of rotation was proved to cause a positive interference on the efficiency of the reactors removal, mainly for lower fiber density, and the increase of this rotation also brought improvements in the organic load removal. The rotation interruption caused en efficiency reduction for the evaluated parameters. Three post-treatments of the effluent of anaerobic reactor were analyzed: flotation, sedimentation (with and without coagulant) and filtration on flexible fibers filter in phase 2. The most suitable post-treatment to be applied along with the anaerobic reactor with flexible fibers was the flotation by separation (without addition of coagulant), which presented removal of 71% of turbidity, 51% of apparent color, 40% of COD, 25% of filtered COD, 34% of total phosphorus and 52% of SST. In the evaluation of the most appropriate chemical-physical post-treatment, the dissolved air flotation presented better results when using the PAC coagulant in the dosage of 14 mg.L-1 of the active principle of Al2O3, with removal efficiency of 84% of turbidity, 73% of apparent color, 50% of total COD, 31% of filtered COD, 45% of total phosphorus and 62% of TSS.

The aim of the study is to determine the nature and utilisation of an Employee Assistance Programme (EAP) in a white-collar work environment, and, more specifically, in a South African context. Information about the research topic was obtained from accumulate records of the Standard Bank's Employee Well-being Programme (EWP), structured interviews which were conducted with eleven EWP practitioners and a union representative, and from self-administered questionnaires which were completed by a sample of 153 of the bank's employees. The study includes an in-depth literature review on EAPs in general and issues such as the nature and scope of the bank's EWP, the extent to which the EWP addresses employees' needs, the nature and extent of the marketing of the EWP, and the extent to which the workforce is utilising the programme, were explored and described. The main findings are that the EWP shows evidence of acceptance by employees as well as a degree of utilisation that compares favourably with local and international trends. It also shows an incongruence between marketing and employee orientation and training initiatives and reveals that programme evaluation efforts are insufficient and could be significantly improved. Accordingly, recommendations have been made pertaining to the needs of employees, employee and union involvement, a multi-disciplinary approach to case management, marketing, training and evaluation with regard to the EWP, an EWP database, and a post-treatment follow-up. / Social Work / M.A. (Social Work)

With the advancements in the field of wireless sensor networks (WSNs), more and more applications require the sensor nodes to have long lifetime. Energy harvesting sources, e.g. thermoelectric generators (TEGs), can be used to increase the lifetime and capability of the WSNs. Integration of energy harvesters into sensor nodes of WSNs can realize self powered systems, providing the possibility for maintenance free WSNs. TEGs can convert the existing temperature differences into electricity. The efficiency of TEGs is directly related to the dimensionless figure of merit (ZT) of materials, which is given as ZT=σS^2 T/k, where σ is the electrical conductivity, S is the Seebeck coefficient, k is the thermal conductivity, T is the temperature and σS^2 is the power factor. Traditional thermoelectric (TE) materials are based on inorganic materials, of which the thermal conductivity is high. Over the past decade, the use of nanostructuring technology, e.g. superlattice, could decrease the thermal conductivity in order to enhance the efficiency of TE materials. However, the high cost and the rigidity of inorganic TE materials are limiting factors. As alternatives, polymer based materials have become the research focus due to their intrinsic low thermal conductivity, high flexibility and high electrical conductivity. Moreover, polymer based materials could be fabricated in solution form, giving the possibility for employing printing techniques hence a decrease in the production cost. Unlike the typical approach, in which secondary dopants are added into PEDOT:PSS solutions to modify the power factor of polymer films, this thesis is focused on a more efficient method to improve TE properties. This thesis demonstrates for the first time that post treatment of PEDOT:PSS films with the secondary dopant DMSO as the medium results in a much larger power factor than the traditional addition method. The post treatment method also avoids the usually required mixing step involved in the addition method. Different solvents were selected to discuss the impact factors in the modification of the power factor by this post treatment approach. The post treatment of PEDOT:PSS films was then extended to utilize a green solvent EMIMBF_4 (an ionic liquid) as the medium. EMIMBF_4 is found to exchange ions with PEDOT:PSS films. As a result, the EMIM^+ cations remain in the films and reduce the oxidation level of PEDOT chains, which affects the Seebeck coefficient and the electrical conductivity. Furthermore, TE materials based on hybrid composites with polymer as the matrix and Te nanostructures as the nanoinclusions were investigated. This thesis successfully developed a green synthesis method to obtain Te nanostructures, in which a non toxic reductant and a non toxic Te sources were used. Well controlled Te nanostructures including nanorods, nanowires and nanotubes were synthesized by wet chemical and hydrothermal synthesis. Those as synthesized Te nanowires were then integrated into PEDOT:PSS solution for composite films fabrication. A high Seebeck coefficient up to 200 μV/K was observed in the composite film. / Mit den Weiterentwicklungen der Drahtlosen Sensornetzwerke (engl. WSN, wireless sensor networks) stellen immer mehr Anwendungen die Forderung einer langen Lebensdauer der Sensorknoten. Energiegewinnungssysteme (engl. Energy Harvesters) wie z.B. thermoelektrische Generatoren (TEGs) können genutzt werden, um die Lebensdauer und Leistungsfähigkeit der WSN zu steigern. Mit der Integration von Energy Harvesters können WSN ohne äußere Stromversorgung realisiert und somit die Möglichkeit zur Wartungsfreiheit geschaffen werden. TEGs liefern Energie durch die Umwandlung einer Temperaturdifferenz in Elektrizität. Die Effektivität der TEG ist direkt verbunden mit der Material-Kennzahl ZT und ist gegeben durch ZT=σS^2 T/k, wobei σ die elektrische Leitfähigkeit ist, S der Seebeck Koeffizient, k die thermische Leifähigkeit, T die Temperatur und σS^2 der Leistungsfaktor. Herkömmliche thermoelektrische (TE) Materialien basieren auf anorganischen Materialien, von denen die thermische Leitfähigkeit hoch ist. Im Laufe des letzten Jahrzehnts konnte durch den Einsatz der Nanostrukturierung die thermische Leitfähigkeit verringern werden um damit die Effizienz von TE-Materialien zu steigern. Die Steifigkeit dieser Materialien ist ein anderer Aspekt. Als Alternative für anorganische TE Materialien sind Polymer basierte TE Materialien zum Fokus der Forschung geworden aufgrund einer intrinsisch niedrigen thermischen Leitfähigkeit, hohen Flexibilität und hohen elektrischen Leitfähigkeit. Des Weiteren können diese Polymere in gelöster Form verarbeitet werden, was die Möglichkeit für den Einsatz von Drucktechnologien und damit geringeren Produktionskosten gibt. Anders als der herkömmliche Ansatz den Leistungsfaktor der Polymerfilme durch die Ergänzung von sekundären Dotanten in PEDOT:PSS Lösungen zu verändern, wurde in dieser Arbeit eine effizientere Methode zur Verbesserung der TE Eigenschaften gesucht. In dieser Arbeit wird zum ersten Mal gezeigt, dass die Nachbehandlung von PEDOT:PSS Schichten mit sekundären Dotanten Dimethylsulfoxid (DMSO) als Medium der Nachbehandlung zu einem viel höheren Leistungsfaktor führt als bei der Zugabemethode und außerdem die sonst erforderliche Mischprocedur vermeidet. Es wurden verschiedene Lösungsmittel ausgewählt um die Einflussfaktoren bei der Modifikation des Leistungsfaktors durch die Nachbehandlung von Polymerschichten zu diskutieren. Die Nachbehandlung von PEDOT:PSS Schichten wurde nachfolgend erweitert um das umweltfreundliche Lösungsmittel EMIMBF4 (eine ionische Flüssigkeit) als das Medium einzusetzen. EMIMBF4 ist bekannt für den Austausch von Ionen mit PEDOT:PSS Schichten, so dass EMIM Kationen in der Schicht verbleiben, die Oxidationsstufe der PEDOT-Ketten senken und damit den Seebeck-Koeffizient und die elektrische Leitfähigkeit beeinflussen. Des Weiteren konzentriert sich diese Arbeit auf TE Materialien basierend auf Kompositen aus Polymeren mit Nanoeinlagerungen. Erfolgreiche Syntheseansätze wurden für Tellur-Nanostrukturen entwickelt, bei denen keine giftigen Reduktionsmittel und keine giftigen Tellur-Quellen zur Verwendung kamen. Es erfolgte die Erzeugung von kontrollierten Tellur-Nanostrukturen, einschließlich Nanostäben, Nanodrähten und Nanoröhren, mit nass-chemischer und hydrothermaler Synthese. Die so hergestellten Nanodrähte wurden dann in PEDOT:PSS Lösungen integriert für die Herstellung von Komposite-Schichten. Dabei konnte ein hoher Seebeck-Koeffizienten, bis zu 200 μV/K, festgestellt werden.