Cellulose Esters
Mostrando 1-12 de 20 artigos, teses e dissertações.
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1. Regenerated Cellulose Membrane from Peanut Shell for Biodiesel Purification
Biodiesel purification by water washing has been proved to be an unattractive process from an economic and environmental point of view. In this work, we propose the use of regenerated cellulose membranes from peanut shell as an alternative in the biodiesel purification. The preparation of the membranes was optimized from a central composite design, resulting
J. Braz. Chem. Soc.. Publicado em: 2020-05
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2. Considerações sobre o preparo de amostras contendo micropoluentes estrogênicos
In this work, the materials used in the recovery of estrogens from aqueous matrices by filtration and solid phase extraction were evaluated. The results showed that glass-fiber filters allow a recovery and repeatability compatible with this type of analysis, whereas cellulose esters lead to significant losses of the analytes, mainly due to adsorption process
Química Nova. Publicado em: 2012
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3. Aplicações e caracterização de ésteres de celulose / Applications and characterization of cellulose esters
Esta tese está dividida em duas partes. Na Parte I, blendas de polietileno maleado (M-PE) e butirato acetato de celulose (CAB) (5-50% em massa) e compósitos de polietileno (PE) ou M-PE e 20% em massa de celulose, acetato de celulose (CA), propionato acetato de celulose (CAP) ou CAB foram preparados em um misturador. As estruturas e propriedades das mistura
Publicado em: 2008
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4. Evaluation of the quality of the water consumed by the population of the District of Sana - Macaé - RJ. / Avaliação da qualidade da água consumida pela população do distrito do Sana Macaé - RJ.
The water is vehicle of pathogenic microoganisms and noxious substances for human health, so its great importance the control of the physiochemical and microbiological characteristics. The aim of this study was to evaluate the quality of the water consumed by the population of the District of Sana - Macaé - RJ, through physiochemical, bacteriological and pa
Publicado em: 2008
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5. Study on the adsorption of horseradish peroxidase (HRP) onto flat surfaces and its catalytic activity / Estudo da adsorção de horseradish peroxidase (HRP) sobre superfícies planas e de sua atividade catalítica
Este trabalho está dividido em duas partes: (i) estudo da adsorção da enzima horseradish peroxidase (HRP) sobre substratos planos (lâminas de Si/SiO2, filmes ASP/Si/SiO2, filmes CABads/Si/SiO2, filmes CABspin/Si/SiO2 e filmes CMCABspin/Si/SiO2) seguida de testes da atividade enzimática da HRP imobilizada sobre estes substratos e (ii) obtenção de olig�
Publicado em: 2008
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6. Ocorrencia de Cryptosporidium spp. e Giardia spp. em hortaliças da região metropolitana de Campinas (SP) : sua relação com a comunidade de trabalhadores e com a area agricola / Occurence of Cryptpsporidium spp., Giardia spp. in vegetables of the metropolitan area of Campinas, SP : her relationship with the wokers community and and with the agricultural area
Cryptosporidium spp. and Gim-dia spp. are waterborne parasites that cause gastroenteritis. They are known for the high incidence of cases and the chemical resistance to treatments and capacity to stay intact for a prolonged time in environment. Today, the great influence of protozoa in several waterborne and foodborne outbreaks, becomes evident that vegetabl
Publicado em: 2008
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7. Reciclagem química do jornal para a produção de membranas de acetato de celulose pelo processo de acetilação homogêneo
In the present work, the chemical recycling of waste newspaper it was done through the homogeneous acetylation process applyed to original and purifyed materials. This materials were characterized by FTIR and TGA. To the sythesis, it was used 48 hours of acetylation to original newspaper (AC48) and 24 hours to purifyed newspaper (AC24). Membranes from this a
Publicado em: 2007
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8. Reciclagem quÃmica do jornal para a produÃÃo de membranas de acetato de celulose pelo processo de acetilaÃÃo homogÃneo
In the present work, the chemical recycling of waste newspaper it was done through the homogeneous acetylation process applyed to original and purifyed materials. This materials were characterized by FTIR and TGA. To the sythesis, it was used 48 hours of acetylation to original newspaper (AC48) and 24 hours to purifyed newspaper (AC24). Membranes from this a
Publicado em: 2007
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9. Purification and properties of an acetylxylan esterase from Fibrobacter succinogenes S85.
An acetylxylan esterase (EC 3.1.1.6) was purified to apparent homogeneity from the nonsedimentable extracellular culture fluid of Fibrobacter succinogenes S85 grown on cellulose. This enzyme had an apparent molecular mass of 55 kDa and an isoelectric point of 4.0. The temperature and pH optima were 45 degrees C and 7.0, respectively. The apparent Km and Vmax
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10. Modification of end phosphate gruops in mono- and oligonucleotides.
A method is described for selective activation of phosphomonoester end groups of oligonucleotides and nucleosidedi-(tri) phosphates via mixed anhydrides with mesitoic acid. Mixed anhydrides are synthesized in high yield and isolated by paper or DEAE-cellulose column chromatography. The ability of such anhydrides to phosphorylate different nucleophilic agents
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11. Optimum Membrane Structures for Growth of Coliform and Fecal Coliform Organisms
The purpose of this study was to determine the optimum membrane filter structure and characteristics for recovery of coliform organisms. Additionally, other factors such as sterilization method and membrane composition were examined. Fecal coliform growth tests with varied samples indicated that the most critical factor in recovery was surface pore morpholog
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12. Isolation and characterization of an enzyme with esterase activity from Micropolyspora faeni.
The isolation and the characterization of one of the enzymes of Micropolyspora faeni that hydrolyzes the substrate N-benzoyl-DL-phenylalanine-beta-naphthyl ester and that seems to be of medical importance are described. This enzyme (enzyme 1) was isolated with an 86-fold purification by using the following seven steps: ammonium sulfate precipitation, gel fil