Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99


Any time

2020 ( 3 )

2019 ( 281 )

2018 ( 446 )

2017 ( 462 )

Custom range...

Search Results: 1 - 10 of 247614 matches for " Tania Lúcia Santos Miranda "
All listed articles are free for downloading (OA Articles)
Page 1 /247614
Display every page Item
Solvent Extraction of Citric Acid with Different Organic Phases  [PDF]
Estêv?o Magno Rodrigues Araújo, Fabrício Eduardo Bortot Coelho, Julio Cézar Balarini, Tania Lúcia Santos Miranda, Adriane Salum
Advances in Chemical Engineering and Science (ACES) , 2017, DOI: 10.4236/aces.2017.73023
Abstract: The present work aimed at the study of citric acid solvent extraction in order to establish the composition of the organic phase and to obtain thermodynamic and kinetic data for the chosen system. Discontinuous extraction experiments in a single stage were performed from a synthetic solution of citric acid, with the typical concentration (10% w/v) observed in industrial fermented musts. Exploratory experiments were carried out using different organic phases in order to select the most suitable solvent phase to further continuous extraction tests in a mechanically agitated column. The selected organic phase composition was: Alamine 336, ExxalTM 13 tridecyl alcohol, and the aliphatic diluent EscaidTM 110. Next, the effects of the contact time and of the concentrations of extractant and modifier on the citric acid extraction were studied. Among the investigated conditions, the best one was 10 minutes of contact time, 30% w/v of Alamine 336, and 10% w/v of ExxalTM 13 tridecyl alcohol. For this condition, the equilibrium isotherm (28°C ± 2°C) was determined, and the equilibrium constant was calculated (36.8 (mol·L-1)-1.5). It was considered that trioctylamine and citric acid complexation reaction occurs mainly with non-dissociated citric acid form, because the aqueous feed solutions’ pH is lower than the citric acid pKa1. It was found that 1.5 molecules of the extractant, on average, are required to react with one citric acid molecule, which can indicate that reactions with different extractant/citric acid ratios occur simultaneously. Next, the rate constants for the direct and inverse reactions, 2.10 (mol·L-1)-1.5·s-1 and 5.69 × 10-2 s-1, respectively, were calculated. Coefficients of determination (R2) values higher than 0.93 were found in these calculations, suggesting that the results obtained using a computer modeling would be very close to those results obtained experimentally. Therefore, the present work provides data required to future modelling, design, and simulation of citric acid solvent extraction processes.
Individual and Combined Effects of the Extractant, Surfactant and Modifier Concentrations on the Droplet Coalescence Time of the Primary Emulsion in the Liquid Surfactant Membrane Extraction Process  [PDF]
Adriane Salum, Lorena da Costa Nascimento, Tania Lúcia Santos Miranda, Leandro Dornellas Sampaio Andrade, Cibele Konzen, Julio Cézar Balarini, Estêv?o Magno Rodrigues Araújo, Fabrício Eduardo Bortot Coelho
Advances in Chemical Engineering and Science (ACES) , 2018, DOI: 10.4236/aces.2018.84014
Abstract: In this work, the individual and combined effects of the extractant, surfactant and modifier concentrations on the droplet coalescence time of the primary emulsion in the liquid surfactant membrane extraction process were evaluated, through emulsification experiments. Adogen 464 was used as extractant (carrier), and Escaid 110, as diluent. Two systems were studied. The first one composed by the extractant, the surfactant and the diluent, and the second one composed by the same reagents, but with the addition of 1-decanol as modifier. It was observed that, when the modifier is not present in the membrane phase, the surfactant not only stabilizes the primary emulsion, but, apparently, it also plays a role similar to that of the alcohol, promoting the solvation of the amine in a low polarity diluent. Furthermore, the extractant, a quaternary amine, helps to stabilize the primary emulsion in systems without a modifier. For membrane phases consisting of 1 or 5% w/w of Adogen 464 and 2% or 5% w/w of ECA 4360, a concentration of 3% w/w of 1-decanol was sufficient to promote the solvation of Adogen 464 in Escaid 110 and to obtain a low droplet coalescence time.
Mulheres na For?a Aérea Brasileira: um estudo sobre as primeiras oficiais aviadoras
Santos, Marina Miranda Lery;Rocha-Coutinho, Maria Lúcia;
Estudos de Psicologia (Natal) , 2010, DOI: 10.1590/S1413-294X2010000300005
Abstract: this article presents part of the results of a study developed with the first brazilian air force women pilots. its objective was to investigate how they experience the career until then prohibited to women, how they perceive the hierarchy and power relations typical of that professional realm, and what they project for their future. we interviewed six women pilots, whose reports were audio recorded, transcribed, and submitted to discourse analysis. such analysis pointed to the fact that contemporary and traditional patterns of behavior coexist. at the same time those women invest in a pioneering professional career and search for financial independence, they continue to dream about marriage and motherhood in traditional formats, reinforcing the idea that women are the main responsible for household care and for raising and educating the children.
Apresenta o: a enfermeira de saúde pública e higiene mental Presentación: la enfermera de salud pública y la higiene mental Presentation: the public health nurse and the mental hygiene
Lúcia Helena Silva Corrêa Louren?o,Fernando Ramos Porto,Tania Cristina Franco Santos
Escola Anna Nery , 2007, DOI: 10.1590/s1414-81452007000400002
Riqueza de espécies de formigas edáficas em planta??o de eucalipto e em mata secundária nativa
Soares, Sandra De Miranda;Marinho, Cidália Gabriela Santos;Della Lúcia, Terezinha Maria Castro;
Revista Brasileira de Zoologia , 1998, DOI: 10.1590/S0101-81751998000400006
Abstract: this investigation was conducted to compare the soil ant fauna of an eucalypt plantation to that of a second growth forest; both áreas located in the zona da mata of minas gerais, brazil. tuna fish, honey and cracker baits were used to collect ants along a transect and pitfall traps were distributed in central 900 m of each site. a total of 64 species belonging to 26 genera were collected in the 12 weekly samples; 54 species were captured in the forest and 45 in the eucalypíus granais plantation. a total of eight species presented frequencies above 10% in at least one area. species richness was higher in the second growth forest. additional studies should be considcred for further generalizations of the results.
Origanum vulgare L. essential oil as inhibitor of potentially toxigenic Aspergilli
Mitchell, Teresa Cristina;Stamford, Tania Lúcia Montenegro;Souza, Evandro Leite de;Lima, Edeltrudes de Oliveira;Carmo, Egberto Santos;
Ciência e Tecnologia de Alimentos , 2010, DOI: 10.1590/S0101-20612010000300029
Abstract: origanum vulgare l. essential oil has been known as an interesting source of antimicrobial compounds to be applied in food conservation. in this study, the effect of o. vulgare essential on the growth of a. flavus, a. parasiticus, a. fumigatus, a. terreus and a. ochraceus was assessed. the essential oil had a significant inhibitory effect on all assayed fungi. mic was 0.6 μl.ml-1 for all fungi, while mfc was in the range of 1.25-2.5 μl.ml-1. the radial mycelial growth of a. flavus and a. parasiticus was strongly inhibited over 14 days at 0.6, 1.25 and 2.5 μl.ml-1 of oil in solid medium. the mycelial mass of all fungi was inhibited over 90% at 0.6 and 0.3 μl.ml-1 in liquid medium, while it was 100% at 1.25 μl.ml-1. the oil in a range of concentrations (0.6 to 2.5 μl.ml-1) was effective in inhibiting the viability and spores germination in a short time of exposure. the main morphological changes caused by the essential oil in a. parasiticus observed under light microscopy were absence of conidiation, leakage of cytoplasm, loss of pigmentation, and disrupted cell structure. these results demonstrated that o. vulgare essential oil produced a significant fungitoxic effect supporting its possible rational use as anti-mould compound in food conservation.
Digestibilidade de dietas suplementadas com fitase para suínos sob diferentes ambientes térmicos
Kiefer, Charles;Santos, Tania Mara Baptista dos;Moura, Mariana de Souza;Silva, Camilla Mendon?a;Lucas, Lúcia dos Santos;Rosa, Elaine Mariza;
Ciência Rural , 2012, DOI: 10.1590/S0103-84782012005000051
Abstract: we conducted a digestibility trial with the aim of evaluate phytase levels on digestibility and nutrient excretion for pigs submitted to thermoneutral conditions and heat stress. we used 24 barrows housed in metabolic cages in climatic chamber, distributed in randomized blocks in a 2x4 factorial design, two environments (23 and 31°c) and four phytase levels (0, 300, 600 and 900uf kg-1 diet), with three replicates and each experimental unit consists of one animal. it was concluded that pigs submitted to high ambient temperatures (31°c) have worse digestibility of protein, phosphorus, calcium, zinc, iron and magnesium and therefore have a higher percentage of nutrients excreted in feces when compared to pigs submitted to thermoneutral environment (23°c). phytase supplementation did not alter the energy value of feed and the digestibility coefficient of protein, but it increases the digestibility coefficient of phosphorus, calcium and magnesium and reduces the percentage of phosphorus and calcium in the faeces of pigs. we recommend the inclusion level of 300uf kg-1 feed, regardless of the environmental thermal condition.
Antimicrobial resistance profiles of enterococci isolated from poultry meat and pasteurized milk in Rio de Janeiro, Brazil
Fracalanzza, Suely Aparecida Pimenta;Scheidegger, Erica Miranda Damásio;Santos, Patricia Faria dos;Leite, Paola Cardarelli;Teixeira, Lúcia Martins;
Memórias do Instituto Oswaldo Cruz , 2007, DOI: 10.1590/S0074-02762007005000120
Abstract: the enterococci are important nosocomial pathogens with a remarkable capacity of expressing resistance to several antimicrobial agents. their ubiquitous nature and resistance to adverse environmental conditions take account for their ability to colonize different habitats and for their potential for easy spreading through the food chain. in the present study we evaluated the distribution of species and antimicrobial susceptibility among enterococcal isolates recovered from food obtained in retail stores in rio de janeiro, brazil. the following species were identified among 167 isolates obtained from poultry meat and 127 from pasteurized milk: enterococcus faecalis (62.6%), e. casseliflavus (17.3%), e. durans (6.5%), e. gallinarum (3.0%), e. gilvus (2.4%), e. faecium (2.0%), e. hirae (1.4%), and e. sulfureus (1.0%). the overall percentages of antimicrobial resistant isolates were: 31.2 % to tetracycline, 23.8% to erythromycin, 11.3% to streptomycin, 4.3% to chloramphenicol, 3.9% to gentamicin, 1.4% to norfloxacin, 1.1% to imipenem, 0.7% to ciprofloxacin, nitrofurantoin, and penicillin, and 0.4% to ampicillin. intermediate resistance was detected in frequencies varying from 0.5% for linezolid to 58.2% for erythromycin. none of the isolates showed resistance to glycopeptides. high-level resistance to aminoglycosides was observed in 13.1% of the isolates. multiresistance was observed in e. faecalis, e. casseliflavus, e. faecium, e. gallinarum, e. durans and e. gilvus.
Reuni?o de diretoras de escolas de enfermagem: um cenário de lutas simbólicas no campo da educa??o em enfermagem (1943-1945)
Almeida Filho, Antonio José de;Santos, Tania Cristina Franco;Baptista, Suely de Sousa;Louren?o, Lúcia Helena Silva Corrêa;
Texto & Contexto - Enfermagem , 2005, DOI: 10.1590/S0104-07072005000400009
Abstract: this historical-social investigation's main objective is the analysis of the symbolic struggle among the different groups of nurses for obtaining the power to announce the authorized brazilian nursing discourse in the meetings of deans of the nursing schools. primary documentary sources were records, memorandums and press releases. secondary documentary sources were nursing related books, articles, theses and dissertations. information analyzed was referenced through some of the concepts from pierre bourdieu's theory of the social world. this investigation proves that in these meetings, alliance agreements for specific interests were established. an ample array of issues can be analyzed from these nursing leadership groups, due to the complexity and individual interests of these groups, which made it difficult to reach a general consensus.
Reuni o de diretoras de escolas de enfermagem: um cenário de lutas simbólicas no campo da educa o em enfermagem (1943-1945)
Antonio José de Almeida Filho,Tania Cristina Franco Santos,Suely de Sousa Baptista,Lúcia Helena Silva Corrêa Louren?o
Texto & Contexto - Enfermagem , 2005,
Abstract: El presente trabajo, de cu o histórico-social, tiene como objetivo principal, la lucha simbólica entre los diversos grupos de enfermeras para conseguir el derecho de enunciar el discurso autorizado sobre la Enfermería Brasile a en las reuniones de las diretorias de las diferentes escuelas de enfermería. En las fuentes documentales primarias, actas, registros, oficios y material periodístico y en las fuentes documentales secundarias, libros, artículos, tesis y disertaciones. Estos datos fueron analizados a según algunos conceptos de la Teoría del Mundo Social de Pierre Bourdieu. Los resultados revelan que en estas reuniones se hacían pactos de alianza para intereses específicos. Se destaca la enorme representatividad ejercida por las enfermeras-religiosas. Fueron diversos los temas que pueden ser analizados a partir de estas reuniones de líderes de la enfermería que, debido a la complejidad y a interéses particulares, presentaron dificultat para estebelecer un consenso dentro del grupo.
Page 1 /247614
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.