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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Energizing Sustainable Livelihoods. A Study of Village Level Biodiesel Development in Orissa, India

Vaidyanathan, Geeta 30 November 2009 (has links)
The present worldwide scenario is one of land-based livelihoods that are increasingly vulnerable to the impacts of climate change. While being committed to environmental goals, India’s National Action Plan on Climate Change released in 2008, reaffirms that maintaining a high growth rate is essential to raising the standard of living of the people. Curbing emissions while maintaining high growth rates and achieving the Millennium Development Goals without increase in fossil fuel consumption, both appear to be paradoxes. Community-based micro energy initiatives have the potential to support productive development without fossil fuel consumption. This study examines small scale, village level biodiesel production for local use, based on unutilized and under-utilized, existing oil seeds in remote rural locations in Orissa, India. The village level biodiesel model is a response to large agro-industrial models that promote plantation of energy crops like jatropha, and to centralized production of biofuels as an alternative to petrodiesel. Village level biodiesel adds value to the large quantity of locally unutilized forest seeds and underutilized short duration oilseed crops like niger that are exported as birdfeed, to fuel livelihoods and boost the local economy. The development of a village level biodiesel model in a participatory manner within an agroecosystem boundary, and its ability to catalyze livelihoods that are sustainable, have been analyzed. Participant observation techniques have been used to develop narrative case studies for three village communities. Methodology for the study is based on Participatory Action Research approaches (Kemmis et al., 2000), where the research process has contributed to community action. The Sustainable Livelihood approach forms an important foundation of this research. A conceptual framework adapted from the original Sustainable Livelihood Framework (Scoones, 1998), to include Complex Systems Thinking (Holling, et al., 1995, Kay, et al., 1999) was used to analyze case studies in two communities of Orissa, India. Informed by results in the first two case communities, the same framework was used to develop a livelihood strategy based on Village Level Biodiesel (VLB), in a third cluster of villages also in Orissa. Three additional inclusions are proposed as a result of the research, to address some gaps in the original framework. These are the concepts of (1) Entitlements (Leach, et al., 1997) to understand power structures, (2) Adaptation Continuum (McGray 2007) to include issues of climate impacts and (3) Rural Livelihood System (Hogger, 2004) as a complex whole relating the inner reality of the farmer to the outer reality of a swiftly globalizing world. Resilience of livelihoods was identified as a key outcome parameter. Three main considerations for assessing sustainability and resilience of livelihoods, as defined by this research are (1) potential for livelihood diversity and intensity, (2) connectedness of the institutions involved in the decision making process, and (3) adaptation – that is resilience of livelihoods in terms of their capacity to resist drivers of vulnerability and confront impacts of climate change. The VLB in Orissa approaches livelihood diversity and intensity through a three-pronged approach consisting of biodiesel fuelled livelihoods, sustainable agriculture and local value addition. Careful attention is given to the specifics of the context in designing the VLB, thus enhancing the adaptive capacity of the technology. In the context of India, with the devolution of power to the local level, the Gram Sabha, or the village governing council, has political powers and the ability to negotiate with the State because of the authority vested in it by the 73rd amendment to the Constitution of India, and can additionally regulate the market at the local level. Leveraging the powers of this entity may provide the VLB with the needed impetus to replicate and move beyond pilot implementations. Obstacles in the implementation and strategies to overcome these have been identified. The challenge to future research and action is to span regional, national and global levels to influence policy makers to take cognizance of and promote the VLB as a viable development alternative to agro-industrial models designed to generate transport fuel.
42

Desempenho e metabolismo de bezerros leiteiros em aleitamento convencional recebendo concentrado inicial contendo glicerol em substituição ao milho / Performance and metabolism of dairy calves on conventional milk feeding receiving initial concentrate containing crude glycerin as a replacement for corn

Gustavo Guilherme Oliveira Napoles 01 February 2013 (has links)
O objetivo deste estudo foi avaliar o efeito da substituição de milho por glicerina bruta no concentrado inicial, sobre o desempenho e alterações no metabolismo energético de bezerros em aleitamento. Vinte e quatro bezerros da raça Holandês recém-nascidos foram alojados em abrigos individuais até a 8a semana de vida, com livre acesso à água, sendo alimentados com 4 litros de sucedâneo/dia e concentrado ad libitum. Os animais foram distribuídos em blocos casualizados de acordo com a data de nascimento e peso ao nascer, e alocados em um dos seguintes tratamentos, de acordo com a inclusão de glicerina em substituição ao milho no concentrado inicial: 1) 0% Glicerina bruta; 2) 5% Glicerina bruta; 3) 10% Glicerina bruta. O aleitamento foi realizado duas vezes ao dia (07 e 17h) com sucedâneo comercial (22% proteína bruta; 19% extrato etéreo). O consumo de concentrado inicial e o escore fecal foram registrados diariamente, enquanto que a pesagem e as medidas de altura na cernelha, perímetro torácico e largura da garupa foram realizadas semanalmente, a partir da segunda semana, até a oitava semana. A partir da segunda semana, foram realizadas colheitas semanais de amostras de sangue, duas horas após o aleitamento da manhã, para determinação das concentrações plasmáticas de glicose, lactato, proteínas totais e &beta;-hidroxibutirato (BHBA). Nas semanas 4, 6 e 8 de idade foram colhidas amostras de fluido ruminal, utilizando-se sonda oroesofágica e bomba a vácuo, para determinação do pH e ácidos graxos de cadeia curta (AGCC). Na oitava semana, se encerrou o período experimental e os animais foram abatidos para avaliação do desenvolvimento do trato digestório superior e de papilas ruminais. O consumo de concentrado inicial, o ganho de peso diário e o peso vivo não apresentaram diferenças (P>0,05) entre os tratamentos. As medidas corporais, não apresentaram diferenças significativas (P>0,05). A média encontrada dos escores fecais durante todo o período experimental sugere baixa frequência de diarreia nos animais. Dentre os parâmetros ruminais avaliados, apenas o propionato e a relação acetato:propionato foram afetados (P<0,05) pelos tratamentos, apresentando menores valores de propionato em animais consumindo concentrado com 5% de glicerina bruta e menor relação acetato:propionato encontrados para os animais recebendo glicerina, este último em resposta ao tipo de fermentação do glicerol. Os parâmetros sanguíneos avaliados (glicose, BHBA, lactato e proteínas totais), não foram afetados pelos diferentes tratamentos (P<0,05), apresentando valores adequados. O peso total do trato digestório superior, os pesos médios de cada compartimento e a capacidade máxima do retículo-rúmen não foram afetados pelos tratamentos, assim como os parâmetros de desenvolvimento do epitélio ruminal. A glicerina pode ser utilizada como ingrediente energético alternativo até a taxa de 10% de substituição ao milho do concentrado inicial de bezerros leiteiros no período de aleitamento sem afetar o crescimento, o desenvolvimento ou o metabolismo do animal. / The purpose of this study was to evaluate the effect of the replacement of corn by crude glycerin in the starter concentrate on performance and energy metabolism of dairy calves. Twenty-four newborns Holstein calves were housed in individual shelters until the eighth week of age, fed 4 liters of milk / day and ad libitum water and concentrate. The animals were distributed in randomized blocks according to the birth date and birth weight, and assigned to one of the following treatments, in accordance with the inclusion of glycerin replacing corn in the starter concentrate: 1) 0% Crude glycerin, 2) 5% Crude glycerin; 3) 10% Crude glycerin. Milk-feeding was performed twice daily (07 and 17h) with commercial milk replacer (22% crude protein, 19% ether extract). The initial feed intake and fecal scores were recorded daily, while weighing and measurements of height at withers, heart girth and hip width were measured from second week to eighth week. From the second week of age, blood samples were collected once a week, two hours after morning feeding, for determination of plasma glucose, lactate, total proteins and &beta;-hydroxybutyrate (BHBA) concentrations. Ruminal fluid was collected at 4, 6 and 8 weeks using an oro-ruminal probe and a suction pump for determination of pH and short-chain fatty acids (SCFA). At the end of eighth week of life, animals were slaughtered to evaluate development of the upper digestive tract and rumen papillae. Feed intake, average daily gain and body weight did not differ (P>0.05) among treatments. No differences was observed for body measurements (P>0.05). The fecal scores suggested low frequency of severe diarrhea in animals. Among the ruminal parameters, only propionate and acetate: propionate ratio were affected (P<0.05) by treatments, with smaller amounts of propionate for animals fed concentrate containing 5% of crude glycerin; and lower acetate: propionate ratio for animals receiving glycerin, because of the type of glycerol fermentation. Blood parameters (glucose, BHBA, total protein and lactate) were not affected by treatments (P<0.05), presenting adequate values. The total forestomach weight, the average weight of each compartment and the maximum capacity of reticulum-rumen were not affected by treatments, as well as the parameters for ruminal epithelium development. Crude glycerin can be used as an alternative energy source replacing corn up to 10% in the starter concentrate for milk-feeding dairy calves without affecting growth, development or animal metabolism.
43

Efeitos de mineralizadores na produção de pigmentos cerâmicos de óxido de ferro resíduo e comercial em matriz de sílica amorfa / Eflect of mineralization in the production of ceramic pigments commercial and waste iron in amorphow silica matriz

Schneider, Aliana Regina 14 October 2012 (has links)
Made available in DSpace on 2016-12-08T17:19:14Z (GMT). No. of bitstreams: 1 Parte 1.pdf: 120753 bytes, checksum: 83faa676dcbe647a5d0a76335228d970 (MD5) Previous issue date: 2012-10-14 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The use of iron oxide in the pigment production is justified by its wide variety of colors, high thermal stability and non-toxic. These oxides may be naturally occurring or synthetic, and currently has progressively expanded the use of industrial byproducts as a source of oxide pigments. Among the processes for the production of pigments, the ceramic process, most widely used by industries has some disadvantages such as high temperatures of calcination. The suggestion to minimize this drawback is the incorporation of substances called mineralization that would act to decrease the temperature of synthesis of these pigments. The purpose of this study was to analyze and produce ceramic pigments of iron oxide with the addition of three types of mineralization in different quantities, as ion source using a chromophore-product industry that already had shown satisfactory results when used in previous work. Moreover, as comparative factor was also produced with iron oxide pigments business under the same conditions of the pigments obtained from the byproduct. Results of thermal analysis demonstrated that the addition of mineralization acted to reduce the onset temperature of the liquid phase, and have been the basis for the choice of different temperatures of calcination. The material resulting from this process was added to porcelain paste and sintered at different temperatures in order to get close as possible to the industrial conditions. According to visual analysis was not possible to observe significant differences between the pigments obtained with the two types of iron oxide, only difference in the intensity, and samples that showed the crystallization of silica generated colors with lighter shades. Finally, the calorimetric analysis performed for the highest amount of pigments with pigments indicated mineralization situated between the red and yellow and high brightness values, indicating clear pigments. / A utilização de óxido de ferro na produção de pigmentos é justificada pela sua ampla variedade de cores, alta estabilidade térmica e atoxidade. Estes óxidos podem ser de origem natural ou sintética, sendo que atualmente vem ganhando espaço o uso de subprodutos industriais como fonte de óxidos pigmentantes. Já entre os processos para produção de pigmentos, o processo cerâmico, mais utilizado pelas indústrias apresenta algumas desvantagens, como as altas temperaturas de calcinação. A sugestão para minimizar este inconveniente é a incorporação de substâncias denominada mineralizadoras que agiriam de forma a diminuir a temperatura de síntese destes pigmentos. O intuito deste trabalho foi produzir e analisar pigmentos cerâmicos de óxido de ferro com a incorporação de três tipos de mineralizadores em quantidades diferentes, utilizando como fonte de íon cromóforo um subproduto industrial que já havia apresentado resultados satisfatórios quando utilizado em trabalho anterior. Além disso, como fator comparativo foi produzido também pigmentos com óxido de ferro comercial nas mesmas condições dos pigmentos obtidos com o subproduto. Resultados de analise térmica demonstraram que a adição de mineralizadores atuou de forma a diminuir a temperatura de início de fase líquida, além de terem sido base para a escolha de diferentes temperaturas de calcinação. O material resultante deste processo foi adicionado à massa porcelânica e sinterizado em diferentes temperaturas com a finalidade de se aproximar o máximo possível das condições industriais. De acordo com analise visual não foi possível observar diferenças significativas entre os pigmentos obtidos com os dois tipos de óxido de ferro, apenas diferença na intensidade, sendo que amostras que apresentaram cristalização da sílica geraram cores com tonalidades mais claras. Por fim, as analises de calorimetria realizada para os pigmentos com maior quantidade de mineralizadores indicaram pigmentos situados entre o vermelho e o amarelo e valores de luminosidade altos, indicando pigmentos claros.
44

Quality assessment and safety of fresh-cut melon coated in chitosan matrix added with microencapsulated bioactive extracted from byproducts of acerola / AvaliaÃÃo da qualidade e seguranÃa de melÃo minimamente processado revestido em matriz de quitosana adicionada de compostos bioativos microencapsulados extraÃdos de subprodutos de acerola

Samira Pereira Moreira 21 July 2014 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / The minimal processing of fruits and vegetables offers the consumer food fresh and practicality. However, these products rapidly lose quality after processing due to physical changes and their consequential biochemical reactions that can reduce the nutritional value and favours besides the growth of deteriorant and pathogenic microorganisms. Thus, this study aimed to develop a system of active packaging, consisting of an microencapsulated antimicrobial edible coating using chitosan added with bioactive compounds extracted from byproducts of processing of acerola (Malpighia emarginata D.C.) for minimally processed melon to maintain the quality and microbiological safety of this product. The parameters extraction of bioactive compounds of lyophilized byproducts (seed, peel and fibers) were optimized as the rotation speed, extraction time, extraction solution and by proportion: extraction solution. The extract showed high content of antioxidants, especially polyphenols. The coating was produced from the 1:1 mixture (v / v) solution of chitosan and 1% ethanolic extract of bioactive compounds, and chitosan itself as the encapsulating material. Two treatments (coated and uncoated melons) each 3 days during 12 days of storage at 10&#730;C  1 were evaluated as attributes of quality, bioactive compounds, total antioxidant activity, spoilage and pathogenic microorganisms (Salmonella spp and Listeria monocytogenes). The results showed that the coating samples provided the melons minor loss of firmness and weight, increased the content of yellow flavonoids and total extractable polyphenols, consequently high total antioxidant activity when compared to control cubes. Moreover, the coating showed antimicrobial activity against bacteria (mesophilic, psicotrophic and lactic), molds and yeasts in coated fruits. The novel product is according to RDC ANVISA 12&#730; whose recommendation for fresh fruits must be absence of Salmonella spp in 25 g. Therefore, this coating is a viable alternative for maintain the quality of minimally processed melons , since it provided better nutrition by maintaining bioactive fruit compounds, the safety, beyond the scope of the life of the product. / O processamento mÃnimo de frutas e hortaliÃas oferece ao consumidor alimentos frescos e prÃticos. Contudo, estes produtos perdem rapidamente a qualidade apÃs o processamento devido Ãs alteraÃÃes fÃsicas e suas conseqÃentes reaÃÃes bioquÃmicas reduzindo o valor nutricional, alÃm de favorecer o crescimento de microrganismos patogÃnicos. Assim, este trabalho objetivou desenvolver um sistema de embalagem ativa, consistindo de um revestimento comestÃvel antimicrobiano para revestimento de melÃo minimamente processado à base de quitosana incorporado de compostos bioativos microencapsulados extraÃdos de subprodutos do processamento de acerola (Malpighia emarginata D.C) visando a manutenÃÃo da qualidade e seguranÃa microbiolÃgica do produto. Os parÃmetros de extraÃÃo dos compostos bioativos dos subprodutos liofilizados (semente, pelÃcula e fibras) foram otimizados quanto a velocidade de rotaÃÃo, tempo de extraÃÃo, soluÃÃo extratora e proporÃÃo subprodutos : soluÃÃo extratora . O extrato apresentou alto teor de compostos antioxidantes, principalmente polifenÃis. O revestimento utilizado nesse estudo foi produzido a partir da mistura na proporÃÃo 1:1 (v/v) de soluÃÃo de quitosana 1% e extrato etanÃlico de compostos bioativos, tendo a prÃpria quitosana como material encapsulante. Dois tratamentos (melÃes revestidos e nÃo revestidos) foram avaliados a cada 3 dias durante 12 dias de armazenamento a 10&#730;C  1 quanto aos atributos de qualidade, compostos bioativos, atividade antioxidante total, microorganismos deteriorantes e patogÃnicos (Salmonella spp e Listeria monocytogenes). Os resultados demonstraram que o revestimento proporcionou aos melÃes menor perda de firmeza e de peso, alÃm de maiores conteÃdos de flavonÃides amarelos e de polifenÃis extraÃveis totais, consequentemente elevada atividade antioxidante total quando comparado ao controle. Foi obsevado aÃÃo antimicrobiana contra bactÃrias (mesÃfilas, psicotrÃficas e lÃticas), bolores e leveduras nos frutos revestidos. O produto apresentou-se em conformidade com a RDC n&#730; 12 da ANVISA cuja recomendaÃÃo para frutas in natura à de ausÃncia de Salmonela spp em 25 g. Portanto, este revestimento à uma alternativa viÃvel para a manutenÃÃo da qualidade de melÃes minimamente processados, uma vez que proporcionou a melhoria nutricional, atravÃs da manutenÃÃo de compostos bioativos da fruta a seguranÃa, alÃm da extensÃo da vida Ãtil desse produto.
45

Utilização do resíduo de sementes processadas de urucum (Bixa orellana L.) na alimentação de suínos em crescimento. / Use of annatto (bixa orellana l.) seed byproduct for growing pigs.

Carlos Eduardo Utiyama 29 June 2001 (has links)
Dois experimentos foram realizados, com o objetivo de avaliar a viabilidade da utilização do resíduo de semente processada de urucum, como um alimento alternativo para suínos na fase de crescimento. O Experimento I constituiu-se de um ensaio de digestibilidade, sendo utilizados quatro fêmeas e quatro machos castrados, mestiços Landrace x Large White, com peso médio de 39,23 kg. Pela técnica de coleta parcial de fezes, utilizando o óxido crômico (Cr2O3) como marcador, determinaram-se os valores dos coeficientes de digestibilidade aparente da energia e da proteína do resíduo de semente processada de urucum, sendo, respectivamente, de 63,2 e 59,7%. Aplicando estes coeficientes sobre os valores de energia bruta (3.740 kcal/kg) e proteína bruta (14,73%), foram determinados os valores de 2.365 kcal/kg e 8,80% para, respectivamente, a energia e a proteína digestíveis do alimento em questão. O valor de energia digestível do resíduo de semente de urucum foi empregado na formulação das rações experimentais do ensaio de desempenho. Foram utilizados 40 suínos (20 machos castrados e 20 fêmeas) com peso médio inicial de 22,49 kg . Os tratamentos consistiram de cinco rações com níveis de 0,0, 2,5, 5,0, 7,5 e 10,0% de inclusão do resíduo de semente processada de urucum, sendo as mesmas isoenergéticas (3.400 kcal/kg de energia digestível), isoprotéicas (18% de proteína bruta) e isolisínicas (0,90%). Água e ração foram fornecidas à vontade durante todo o período experimental de 35 dias. O delineamento experimental foi o de blocos casualizados, com quatro repetições por tratamento e dois animais (um macho castrado e uma fêmea) por unidade experimental (baia). As pesagens dos animais e o cálculo do consumo diário de ração (CDR), ganho diário de peso (GDP) e conversão alimentar (CA) foram feitos semanalmente. Não houve diferença (P>0,05) entre os níveis de inclusão de resíduo de semente de urucum na dieta sobre o CDR, GDP e CA dos animais. Mesmo após a decomposição dos graus de liberdade dos tratamentos em seus componentes linear, quadrático, cúbico e de quarto grau pelos polinômios ortogonais, não foi detectada (P>0,05) qualquer tendência das referidas variáveis. Assim, pode-se concluir que, em relação a uma dieta padrão de milho e farelo de soja, uma vez mantidas as dietas isoenergéticas, isoprotéicas e isolisínicas, o resíduo de semente de urucum pode ser incluído até o nível de 10%, sem influenciar o desempenho dos suínos em crescimento (22,5 a 53,5 kg PV). / The purpose of this study was to evaluate the use of annatto (Bixa orellana L.) seed byproduct as an alternative feed ingredient for growing pig. In Experiment I, eight Landrace x Large White crossbred growing pigs (four barrows and four gilts), averaging 39.23 kg live weight, were used for digestibility assay. The method was the partial faeces collection, using the chromium oxide (Cr2O3) as fecal marker. The determined apparent digestibility coefficients of energy and protein were, respectively, 63.2 and 59.7%, resulting in 2,365 kcal/kg of digestible energy and 8.8 % of digestible protein. In Experiment II, forty pigs were assigned to five treatments, in a randomized complete block design based on initial live weight and genetic group (30 Seghers and 10 Landrace x Large White crossbred pigs). The five treatments consisted of dietary levels of 0.0, 2.5, 5.0, 7.5 and 10. 0% of annatto seed byproduct. All experimental diets were formulated to contain the same levels of digestible energy (3,400 kcal/kg), crude protein (18.0% CP) and total lysine (0.90%). Pigs were housed in 20 pens, with two pigs (a barrow and a gilt) per pen (experimental unit), and four replications per treatment. Feed and water were given ad libitum to pigs during all 35-day experimental period. The live weight and the data of feed intake per pen were registered every week. Pig performance data, such as daily feed intake (DFI), average daily gain (ADG) and feed conversion (FC) were analyzed by polynomial regression and the treatment means were compared by Tukey test. No treatment effects were observed on DFI, ADG and FC. Therefore, it can be concluded that the annatto seed byproduct can be used up to 10% in growing pig diets, adjusted for the same levels of energy and protein.
46

Remoção de substâncias húmicas em tratamento de água por meio de pré-oxidação e dupla filtração / Removal of humic substances in water treatment through preoxidation and double filtration

Giovana Kátie Wiecheteck 18 March 2005 (has links)
Para estudar a remoção de substâncias húmicas da água, foi utilizada uma instalação piloto de pré-oxidação e dupla filtração com filtro ascendente de areia grossa (FAAG) e filtro rápido descendente (FRD). Ozônio, peróxido de hidrogênio, peroxônio, tricloro-s-triazina-triona, dióxido de cloro, permanganato de potássio e hipoclorito de sódio foram utilizados como pré-oxidantes. A água de estudo era proveniente do Ribeirão do Feijão (São Carlos - SP) com adição de extrato de substâncias húmicas até cor verdadeira de 90 a 110 uH. O trabalho experimental foi realizado em quatro etapas: i) extração de substâncias húmicas; ii) ensaios em reatores estáticos; iii) ensaios na instalação piloto em escoamento contínuo sem pré-oxidação com taxas de filtração no FAAG entre 120 e 240 m3/m2d e no FRD entre 160 e 280 m3/m2d e; iv) ensaios na instalação piloto em escoamento contínuo sem e com pré-oxidação com taxas de filtração de 180 m3/m2 d no FAAG e 280 m3/m2d no FRD. Houve eficiência de remoção de substâncias húmicas nos ensaios sem pré-oxidação e com variação de taxas de filtração, eventualmente, observou-se residual de alumínio maior que 0,2 mg/L no efluente do FRD. Nos ensaios com pré-oxidação obteve-se redução de 50% na dosagem de coagulante, resultando em menores concentrações de alumínio residual nos filtros, e redução de 43 a 63% na perda de carga final do FAAG, comparando-se com o ensaio sem pré-oxidação. As amostras pré-oxidadas com ozônio apresentaram maiores concentrações de ácidos haloacéticos. No efluente do FRD, observou-se aumento das concentrações de trialometanos com o aumento do pH. Nos ensaios com dióxido de cloro e permanganato de potássio observaram-se menores concentrações de subprodutos. / A pilot plant of preoxidation and double filtration with coarse sand upflow filter (CSUF) and downflow filter (DF) was used with the purpose of removing humic substances of the water. Ozone, hydrogen peroxide, peroxone, chlorine, chlorine dioxide and potassium permanganate were used as preoxidants. The water of study was originating from Ribeirão Feijão (São Carlos - SP) with addition of extract of humic substances until true color from 90 to 110 uH. The experimental work was accomplished in four stages: i) extraction of humic substances; ii) tests in static reactors; iii) runs in the pilot plant in continuous flow without preoxidation with filtration rates in the upflow filter between 120 and 240 m3/m2d and in the downflow filter between 160 and 280 m3/m2d and; iv) runs in the pilot plant in continuous flow with and without preoxidation with filtration rates of 180 m3/m2d in the upflow filter and 280 m3/m2d in the downflow filter. There was efficiency of removal of humic substances in the runs without preoxidation with variation of filtration rates, but the effluent of the downflow filter presented aluminum residual larger than 0,2 mg/L. In the runs with preoxidation a reduction in the coagulant dosage of 50% was observed and consequently smaller concentration of aluminum residual in the effluent of the downflow filter, and reduction of 43 to 63% in the final load loss in the upflow filter, compared with the run without preoxidation. The preoxidaded water with ozone was verified higher concentration of haloacetic acids. In the effluent of the downflow filter was observed increase of trihalomethane concentrations with the increase of the pH. In the runs with chlorine dioxide and potassium permanganate were observed lower concentrations of byproducts.
47

Contribution of organic UV filters to the formation of disinfection byproducts in chlorinated seawater swimming pools : occurrence, formation and genotoxicity

Manasfi, Tarek 22 September 2016 (has links)
La désinfection de l’eau de piscine est essentielle pour prévenir la propagation de maladies infectieuses. Cependant, les désinfectants réagissent avec les composés organiques présents dans l’eau y compris ceux introduits par les baigneurs, tels que les fluides corporels et les crèmes solaires, conduisant à la formation de sous-produits de désinfection (SPD) associés à des effets néfastes sur la santé. Le devenir des filtres UV organiques, présents dans les crèmes solaires et les produits de soins personnels, dans les piscines d'eau de mer chlorées est peu connu. Les objectifs de la présente étude étaient d'étudier la réactivité des filtres UV organiques dans l'eau de mer chlorée, d’identifier les SPD générées par les filtres UV, d'analyser l’occurrence des SPD dans les piscines d'eau de mer, et d'examiner leur génotoxicité. Des expériences de chloration ont été menées dans l'eau de mer reconstituée sur cinq filtres UV couramment utilisés : l’oxybenzone (OXY), le dioxybenzone (DIOXY), l’avobenzone (AVO), l’octyl méthoxycinnamate (OMC), et l’octocrylène (OC). Tous les composés étudiés sauf l’OC ont été dégradés conduisant à la formation de SPD bromés pour lesquels des schémas réactionnels ont été proposés. L'occurrence de ces SPD a été étudiée dans les piscines d'eau de mer où des SPD bromés ont été quantifiés. La génotoxicité de l’hydrate de bromal (BH), l’un des SPD généré par OXY et DIOXY et détecté dans les piscines d'eau de mer, a été évaluée. BH a induit une activité génotoxique dans le test d'Ames et l'essai de comète. Cette étude montre que les filtres UV peuvent agir comme précurseurs pour la formation de SPD génotoxiques dans l’eau de mer chlorée. / Disinfection of swimming pool water is critical to prevent outbreaks of infectious diseases. However, disinfectants react with organic compounds present in water, including anthropogenic inputs (e.g. body fluids, sunscreens), leading to the formation of disinfection byproducts (DBPs) that have been linked to adverse health effects. Little is known about the fate of organic UV filters, present in sunscreens and personal care products, when introduced into chlorinated seawater swimming pools. The aims of the present study were to investigate the reactivity of five commonly used organic UV filters in chlorinated seawater, identify DBPs generated from the UV filters, analyze the occurrence of these DBPs in seawater swimming pools, and examine their genotoxicity. Chlorination experiments were conducted to analyze the reactivity of the UV filters oxybenzone (OXY), dioxybenzone (DIOXY), avobenzone (AVO), octyl methoxycinnamate (OMC), and octocrylene (OC) in reconstituted seawater. All the studied UV filters except OC were degraded in chlorinated seawater resulting in the formation of brominated DBPs. Based on the identified byproducts, transformation pathways were proposed. The occurrence of the identified DBPs was investigated in seawater pools. Several brominated DBPs were identified in seawater pool samples. The genotoxicity of bromal hydrate (BH), which was generated by the benzophenone UV filters OXY and DIOXY and detected in the investigated seawater pools, was assessed. BH induced genotoxic activity in the Ames test and in the comet assay. Overall, this study shows that UV filters can act as precursors for the formation of genotoxic DBPs in chlorinated seawater pools.
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Analyses de la disponibilité économique des métaux rares dans le cadre de la transition énergétique / Study of economic availability related to rare metals in the context of the energy transition

Fizaine, Florian 06 October 2014 (has links)
Un nombre croissant d’études académiques et de rapports d’organismes internationaux relèvent une dépendance accrue des nouvelles technologies de l’énergie vis-à-vis d’une catégorie de ressources souvent prénommés métaux rares. Parallèlement, il se forme depuis plusieurs années des inquiétudes sur la disponibilité économique de ces métaux pour opérer la transition énergétique nécessaire à la lutte contre le réchauffement climatique. Cette thèse a donc pour objectif de souligner l’ensemble des contraintes et des risques qu’implique l’usage fréquent et généralisé de ces métaux dans les nouvelles technologies de l’énergie. Une première partie de la thèse est consacrée aux indicateurs et aux théories reliées à la disponibilité économique de long terme d’une ressource non renouvelable tout en faisant apparaitre un ensemble de traits communs partagés par les métaux rares. La seconde partie de cette thèse démontre les risques attachés à une absence d’élasticité prix de l’offre de métaux rares du fait d’une contrainte de sous-produit. Elle offre également une analyse approfondie des causes et des conséquences relatives à l’absence de marché à terme pour la quasi-totalité de ces métaux rares. Enfin, son dernier chapitre propose d’explorer la liaison très forte existant entre le secteur de l’énergie et le secteur des métaux. Il y est démontré que cette connexion s’accentue et qu’elle implique la possibilité d’un cercle vicieux entre des énergies toujours moins concentrées (avec un contenu en métaux grandissant) et des métaux qui consomment toujours plus d’énergie sous l’effet de leur épuisement. / A growing number of academic studies and international organizations reports have noticed an increasing dependency of new energy technologies on a specific class of natural resources often called minor metals. For several years, worries about economic availability of these metals in order to realize the energy transition have appeared. This thesis aims at underline the broader risks and constraints involved by general use of these metals in new energy technologies. A first part of this thesis is devoted to theories and indicators related to the depletion of non renewable resources. This part also shows that minor metals share many characteristics and that they can form a group of metal consistent. In a second part, this thesis addresses the issues linked to the absence of price elasticity for the supply of minor metals due to the byproduct constraint. Another chapter offers an analysis of causes and consequences connected to the absence of futures markets for almost all minor metals. Finally, a last chapter highlights the strong link existing between the energy sector and the metals sectors. This connection is increasing and can create a vicious circle between energies which are less and less concentrated and metals which consume more and more energy due to their depletion.
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Utilização de glicerol na dieta de suínos em crescimento e terminação / Use of dietary levels of glycerol in growing and finishing pigs

Bernardo Berenchtein 25 August 2008 (has links)
O presente trabalho teve como objetivo avaliar níveis de 0, 3, 6 e 9% de glicerol na dieta de suínos em crescimento e terminação por meio do desempenho, das características de carcaça e da qualidade da carne. Foram utilizados 64 animais da genética Topigs com peso médio inicial 33,27 ± 4,66 kg, distribuídos em 32 baias de acordo com o sexo e peso inicial, em um delineamento em blocos casualizados com oito repetições (blocos) por tratamento. Em cada uma das três fases, crescimento I (33,27 a 65,00 kg), crescimento II (65,00 a 85,00 kg) e terminação (85,00 a 99,97 kg), os animais receberam rações isonutritivas e água à vontade. Ao atingirem o peso vivo médio de 99,97 ± 1,92 kg, os animais foram abatidos e as carcaças avaliadas para o rendimento de carcaça quente, comprimento de carcaça, espessura de toicinho, área de olho de lombo e calculada a relação gordura/carne. Amostras do músculo Longissimus dorsi foram retiradas para medição do pH, cor e perda de água por gotejamento. A adição de glicerol proporcionou redução apenas no ganho diário de peso (P=0,04) durante as fases de crescimento I e II. De modo geral, o glicerol, um subproduto da produção de biodiesel, pode ser utilizado como ingrediente energético de rações de suínos em crescimento e terminação até o nível de 9%, sem afetar sensivelmente o desempenho, as características de carcaça e a qualidade da carne dos animais. / The purpose of this work was to evaluate the effect of 0, 3, 6 and 9% of glycerol in growing and finishing pig diets on performance, carcass traits and meat quality. Sixty-four pigs of Topigs genetic with 33.27 ± 4.66 kg initial live weight were allotted to 32 pens, according to sex and initial weight in a randomized complete block design with eight replications (blocks) per treatment. In each of three phases, growing I (33.27 to 65.00 kg), growing II (65.00 to 85.00 kg) and finishing (85.00 to 99.97 kg), diets and water were given ad libitum to animals. When pigs reached 99.97 ± 1.92 kg live weight, they were slaughtered and data of hot carcass yield, carcass length, backfat thickness, loin eye area and fat area/loin eye area ratio were registered. Samples of Longissimus dorsi were taken to determine pH, colour and water drip loss. Added glycerol depressed average daily gain (P=0.04) only during growing I and II periods. Overall, glycerol, a by-product of biodiesel production, can be used as energy source of growing and finishing pig diets up to 9% without affecting performance, carcass traits and meat quality of animals.
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Uso do frit de laranja em dietas para tilápia-do-Nilo desempenho produtivo e sistema antioxidante /

Vicente, Igor Simões Tiagua January 2017 (has links)
Orientador: Margarida Maria Barros / Resumo: Foi avaliada a capacidade antioxidante do frit de laranja (OF) no desempenho produtivo, perfil hematológico e atividade das enzimas antioxidante na tilápia-do-Nilo submetidas ao estresse térmico. Um grupo de 440 tilápias-do-Nilo machos (31.7g ± 0.34) foram distribuidos em 40 aquários 250 – L (11 peixes/caixa) e arraçoados com cinco dietas práticas com diferentes níveis de OF 0, 0.2, 0.4, 0.6, 0.8% OF por 70 dias. As dietas foram formuladas para conter 26% de proteína digestível e 14.24 MJ de energia digestível kg-1. Após o período de alimentação foi determinado o desempenho produtivo, perfil hematológico, e atividade das enzimas antioxidante. Após, os peixes foram submetidos ao estresse térmico (32°C) durante três e o mesmo perfil hematológico e atividade das enzimas antioxidante foram determinados. Não houve diferença estatística no desempenho produtivo entre os tratamentos. Peixes alimentados com as dietas 0 Of demonstraram menores valores no perfil hematológico após o estresse térmico (P < 0.05). Os peixes alimentados com dietas que continham 0.6 OF apresentaram menor taxa de hematócrito e os alimentados com 0.8 OF menores taxas de hemoglobin e hematócrito após o desafio de estresse térmico. Peixes alimentados com dietas que continham 0.4 OF demonstraram valores mais baixos de volume corpuscular médio (VCM) e maiores valores de concentração de hemoglobina corpuscular media (CHCM) quando comparados antes e após estresse térmico. As dietas com inclusão de frit de laranja det... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The antioxidant capacity of dietary orange frit (OF) on growth, hematological profile and antioxidant enzymes activity of Nile tilapia subjected to heat-induced stress (HIS) was analyzed. A group of 440 male Nile tilapia (31.7g ± 0.34) was randomly distributed in 40 250-L aquaria (11 fish/tank) and fed five practical diets with graded levels of OF at 0, 0.2, 0.4, 0.6 and 0.8% OF orange frit kg-1 diet for 70 days. The diets were formulated to contain 26% digestible protein and 14.24 MJ digestible energy kg-1. After the feeding period, growth performance, hematological profile and antioxidant enzymes activity were determined. Then, fish were subjected to HIS (32°C) for three days and the same hematological profile and antioxidant enzymes activity were determined. There was no statistical difference for growth performance among treatments. Fish fed 0 OF diet showed lower hematological profile after HIS (P < 0.05). Fish fed 0.6OF presented lower hematocrit and fed 0.8 OF lower hemoglobin and hematocrit after HIS. Fish fed 0.4 OF showed the lowest mean corpuscular volume (MCV) and the highest mean corpuscular hemoglobin concentration (MCHC) comparing the vales before and after HIS. Dietary orange frit determined different activities (P < 0.05) for catalase before HIS. Fish fed 0 OF diet showed the highest activity and 0.2 OF the lowest. After HIS fish fed 0 OF and 0.2 OF showed the lowest activity and 0.6 OF the highest (P < 0.05). A comparison of the values before and after HIS s... (Complete abstract click electronic access below) / Mestre

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