Sample records for ethanol
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1

Etanol e biodiesel como recursos energéticos alternativos: perspectivas da América Latina e da Ásia/ Ethanol and biofuels as alternatives energetic sources: Latin-American e Asian perspectives

Masiero, Gilmar; Lopes, Heloisa
2008-12-01

Resumo em português Este trabalho apresenta as perspectivas latino-americanas e asiáticas na emergente indústria dos biocombustiveis. As possibilidades brasileiras de participação na indústria e no comércio internacional de etanol e de biodiesel são discutidas. Uma questão sobre os possíveis parceiros "estratégicos" do Brasil neste setor é levantada: os enormes mercados consumidores de países desenvolvidos ou os emergentes e também famintos consumidores asiáticos de energia? Resumo em inglês This paper presents Latin American and Asian perspectives on the biofuels emerging industry. The Brazilian's possibilities of participation on this industry evolution and the involvement on the world trade for ethanol and biodiesel are discussed. Also, an investigation about who will be the main "strategic" partners of Brazil in this sector is made: the huge consumer markets of developed countries or the emerging and also hungry consumers of energy Asian economies?

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2

Produção de etanol a partir de torta de mamona (Ricinus communis L.) e avaliação da letalidade da torta hidrolisada para camundongos/ Ethanol production from castor bean cake (Ricinus communis L.) and evaluation of the lethality of the cake for mice

Melo, Walber Carvalho; Silva, Daniele Barreto da; Pereira Jr., Nei; Anna, Lídia Maria Melo Santa; Santos, Alexandre Soares dos
2008-01-01

Resumo em inglês The castor bean cake is rich in starch (48 ± 0.53%) and bears a problem linked to the occurrence of a toxic protein (ricin). The chemical hydrolysis (ratio solid:liquid = 1:6; H2SO4= 0.1 mol L-1; 120 °C; 40 min) generated a medium with 27 g L-1 of reducing sugars (hydrolysis efficiency= 32%). The hydrolyzed product was fermented and produced 11 g L-1 of ethanol (volumetric productivity=1.38 g L-1 h-1 and ethanol yield on substrate consumed=0.45 g g-1). In vivo experiments (DL50) revealed a reduction of roughly 240 times in the CBC toxicity (2.11 µg g-1).

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3

Reações de Etanol com CO/H2 na Presença do Sistema Catalítico Ru(acac)3/I-/ Ethanol, reactions with co/h2 in the presence of the ru(acac)3/i- catalytic system

Trabuco, Elizeu
1997-06-01

Resumo em inglês The hydrocarbonylation reaction of ethanol with a CO/H2 mixture assisted by Ru(acac)3/iodide was investigated. Bronsted and Lewis acids and iodides salt were used as homogeneous promoters. The etherification reaction was the main reaction under typical acidic conditions of the catalytic system. When a hydrocarbon solvent (toluene) was added to the initial reaction, the alcohol conversion and the carbonylation products were increased. The catalytic activity of the Bronsted (mais) acids (conv. EtOH = 71-92%) was higher than that of the Lewis acids promoters (conv. EtOH = 65-85%). The salt present the lower catalytic activity among the promoters used. The long time reaction carried out with ethanol showed an increase of the product selectivity of the homologation and carbonylation reactions while the etherification reaction selectivity decreased. The recycled ether led to 60-65% ethanol conversion to C5 and C6 products. The main catalytic species are H+[Ru(CO)3I3]-, [HRu3(CO)11]- and [HRu(CO)4]-. The first one is active in the carbonylation and homologation reactions of alcohols while the two others take part only in the homologation reaction.

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4

Determinação de etanol e voláteis relacionados em sangue e fluido oral por microextração em fase sólida em headspace associada à cromatografia gasosa com detector de ionização em chama/ Determination of ethanol and related volatile compounds in blood and oral fluid by headspace solid-phase micro extraction associated to gas chromatography with flame-ionization detector

Feltraco, Lílian de Lima; Antunes, Marina Venzon; Linden, Rafael
2009-01-01

Resumo em inglês The aim of this study was to validate a method for the determination of acethaldehyde, methanol, ethanol, acetone and isopropanol employing solid-phase microextraction associated to gas chromatography with flame ionization detection. The operational conditions of SPME were optimized by response surface analysis. The calibration curves for all compounds were linear with r² > 0.9973. Accuracy (89.1-109.0%), intra-assay precision (1.8-8.5%) and inter-assay precision (2.2-8. (mais) 2%) were acceptable. The quantification limit was 50 µg/mL. The method was applied to the meaurement of ethanol in blood and oral fluid of a group of volunteers. Oral fluid ethanol concentrations were not directly correlated with blood concentrations.

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5

Importância do etanol na atenuação natural de águas subterrâneas impactadas por gasolina/ Importance of ethanol on natural attenuation of groundwater impacted by gasohol

Nunes, Cristina Cardoso; Corseuil, Henry Xavier
2007-09-01

Resumo em português Nesse estudo, foram avaliados os resultados de um experimento de derramamento controlado de gasolina brasileira em água subterrânea durante 6,5 anos de monitoramento. A exaustão do etanol, aos 32 meses de monitoramento, e a significativa redução de mais de 90% da massa máxima dos compostos BTEX dissolvidos no meio, aos 79 meses, associadas ao uso dos receptores de elétrons e acúmulo de seus subprodutos metabólicos, demonstraram a eficácia da atenuação natural (mais) monitorada para contaminações de águas subterrâneas sem riscos imediatos a receptores críticos. Constatou-se ainda que a biodegradação do etanol permitiu a formação de uma biobarreira natural que, após a sua completa degradação, acelerou a taxa de biodegradação dos BTEX e impediu o avanço da pluma destes contaminantes. Resumo em inglês In this study, results of 6.5 years of a controlled release experiment with Brazilian gasoline in groundwater were evaluated. Ethanol exhaustion after 32 months and the significant dissolved BTEX mass reduction of more than 90% after 79 months, associated with the electron acceptors use and their metabolic byproducts accumulation, demonstrated the efficiency of monitored natural attenuation for groundwater contamination without immediate risk to receptors. Moreover, ethan (mais) ol degradation provided a natural biobarrier formation that increased BTEX biodegradation rate and prevented the BTEX plume expansion.

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6

Eletro-oxidação de etanol sobre eletrocatalisadores PtRh/C, PtSn/C e PtSnRh/C preparados pelo método da redução por álcool/ Electro-oxidation of ethanol on PtRh/C, PtSn/C and PtSnRh/C electrocatalysts prepared by alcohol-reduction process

Oliveira Neto, A.; Dias, R. R.; Ribeiro, V. A.; Spinacé, E. V.; Linardi, M.
2006-01-01

Resumo em português Os eletrocatalisadores PtRh/C, PtSn/C e PtSnRh/C foram preparados pelo método da redução por álcool e caracterizados pelas técnicas de EDX, difração de raios X e voltametria cíclica. A eletro-oxidação direta de etanol foi estudada por voltametria cíclica utilizando a técnica do eletrodo de camada fina porosa. Na região de interesse para aplicações em células a combustível a etanol direto (0,3 a 0,4 V) os eletrocatalisadores PtSn/C e PtSnRh/C se mostraram mais ativos que os eletrocatalisadores PtRh/C. Resumo em inglês PtRh/C, PtSn/C and PtSnRh/C electrocatalysts were prepared by the alcohol-reduction process and characterized by EDX, XRD and cyclic voltammetry. The electro-oxidation of ethanol was studied by cyclic voltammetry using the thin porous coating technique. In the region of interest for direct ethanol fuel cell (0.3-0.4V) PtSn/C and PtSnRh/C eletrocatalysts were more active than PtRh/C electrocatalysts.

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7

Avaliação da influência do etanol sobre o grau de volatilização BTEX em solos impactados por derrames de gasolina/etanol/ Evaluation of the ethanol influence over the volatilization grade of BTEX in soil impacted by gasoline/ethanol spills

Finotti, Alexandra Rodrigues; Teixeira, Cláudia Echevenguá; Fedrizzi, Franciele; Calgliari, Joice; Nascimento Filho, Irajá do
2009-12-01

Resumo em português O principal objetivo deste trabalho foi a avaliação quantitativa da influência do etanol sobre a volatilização de BTEX (benzeno, tolueno, etilbenzeno e xilenos) em mistura de gasolina e etanol anidro 25% (v/v) em colunas experimentais, que simularam solos contaminados com gasolina pura e gasolina/etanol. Todos os BTEX apresentaram expressivo aumento das taxas de volatilização na coluna contendo a mistura gasolina/etanol. Porém, em termos percentuais, o maior e men (mais) or aumento nas taxas de volatilização foi observado para tolueno e benzeno, respectivamente. Em amostras de controle, com o percentual de etanol variando entre 0 e 25%, não foi observado aumento no grau de volatilização do etilbenzeno, enquanto que o grau de volatilização dos xilenos foi reduzido. Estes resultados sugerem que, além de forças de interação intermoleculares, efeitos de interação líquido/estrutura do solo podem estar exercendo importante papel na volatilização dos BTEX. Resumo em inglês The main objective of this paper was the quantitative evaluation of the ethanol's influence about the volatilization of BTEX (benzene, toluene, ethylbenzene and xylenes) in a mixture of gasoline and anhydrous ethanol 25% (v/v) in experimental columns that simulated soil contamination with gasoline/ethanol. All the BTEX presented expressive increase of volatilization rates in the gasoline-ethanol column. However, in terms of percentage, the highest and lowest volatilizatio (mais) n grades were observed for toluene and benzene, respectively. In batch tests (control samples), with mixtures of gasoline ethanol with 0 and 25% (v/v) in ethanol, no increase of the volatilization grade was observed for ethylbenzene and the volatilization grade for xylenes was reduced. Matrix effects seem to be, besides the intermolecular interaction forces, important contributions for the volatilization grade of BTEX in this kind of sample.

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8

Desidratação de etanol sobre material nanoestruturado do tipo LaSBA-15/ Ethanol dehydration over LaSBA-15 nanostrutured material

Luz Jr, Geraldo E.; Melo, Ana C. R.; Lima, Stevie H.; Araujo, Antônio S.; Fernandes Jr., Valter J.
2010-01-01

Resumo em inglês La-incorporated SBA-15 mesopourous molecular sieves (LaSBA-15) were directly synthesized with aim to convert ethanol to ethylene. The samples were characterized by XRD, XRF, nitrogen sorption and acidity, by thermodesorption of n-buthylamine. The results have indicated that all the samples have showed high ordered mesostructure with a large average pore size, and that the lanthanum incorporation has caused an increase in the acidity of the SBA-15. The LaSBA-15 samples hav (mais) e improved, with low deactivation rate, the conversion of the ethanol to water, ether, acetaldehyde and ethylene. In addition, they have increased the ethylene selectivity.

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9

Produções de ácido acético, etanol e dos isômeros óticos do ácido lático por linhagens de Lactobacillus isoladas de fermentações alcoólicas industriais/ Production of acetic acid, ethanol and optical isomers of lactic acid by Lactobacillus strains isolated from industrial ethanol fermentations

Costa, Vanessa Moreira; Basso, Thiago Olitta; Angeloni, Luis Henrique Poleto; Oetterer, Marilia; Basso, Luiz Carlos
2008-04-01

Resumo em português Avaliaram-se no presente trabalho, as produções de etanol e dos ácidos acético e lático, bem como das proporções dos isômeros óticos D(-) e L(+) desse último, por 17 linhagens de Lactobacillus isoladas de fermentações industriais de produção de etanol. As linhagens foram crescidas a 32ºC por 24 horas, em meio contendo 1% de glucose, 1% de frutose, 1% de extrato de levedura, sais nutrientes (K, Mg e Mn) e tampão fosfato. Foram estimados os teores de ácido (mais) lático, ácido acético e etanol mediante cromatografia líquida de alta eficiência, assim como dos isômeros óticos D(-) e L(+) do ácido lático mediante espectrofotometria ao ultra-violeta, empregando desidrogenases láticas estereoespecíficas. O crescimento bacteriano foi inferido pela absorvância a 600 nm. Os resultados obtidos mostraram, pelos perfis de excreção dos metabólitos, a presença de 8 linhagens homofermentativas obrigatórias (produzindo unicamente ácido lático), 8 linhagens heterofermentativas obrigatórias (com produções de ácidos lático, acético e etanol) e 1 linhagem supostamente heterofermentativa facultativa. Observou-se também, em relação à formação dos estereoisômeros, que 12 linhagens foram incluídas no grupo DL, 4 no grupo L e 1 no grupo D. Os resultados permitem concluir que os Lactobacillus que contaminam processos fermentativos industriais de produção de etanol, podem se apresentar nos 3 biotipos fermentativos e produzindo as mais variadas proporções dos dois estereoisômeros do ácido lático, com relevantes implicações biotecnológicas. Este é o primeiro relato sobre as produções dos isômeros óticos do ácido lático por bactérias do gênero Lactobacillus isoladas de fermentações industriais baseadas na cana-de-açúcar. Resumo em inglês The aim of the present work was to evaluate the metabolism type of 17 Lactobacillus strains isolated from industrial ethanol fermentation plants. The strains were grown at 32°C for 24 hours on a mixture of equal amounts of glucose and fructose as the carbon source, and supplemented with yeast extract, mineral nutrients and buffer. Bacterial growth was estimated by absorbance at 600nm and the main end products of bacterial metabolism (lactate, acetate and ethanol) were (mais) measured by high performance liquid chromatography, while the stereoisomers, D(-)- and L(+)-lactate, were assayed by an enzymatic methodology using stereospecific lactate-dehydrogenases. According to the results, all the three types of metabolism were found among the bacteria investigated: obligately homofermentative (8 strains), facultative heterofermentative (1 strain) and obligately heterofermentative (8 strains). The results have showed a predominance of DL strains regarding the stereoisomers production, but it was also found strains producing a single type of the isomeric form. These findings suggest the possibility to explore the lactobacilli biodiversity in fuel ethanol fermentation plants for lactate production of chemically pure optical isomers. This is the first report on lactic acid isomers formation by Lactobacillus strains isolated from sugar cane based-industrial fermentations.

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10

Injeção percutânea de etanol no tratamento de nódulos tiroidianos sólidos, císticos e autônomos/ Percutaneous ethanol injection for treatment of solid, cystic and autonomous thyroid nodules

Bianchini, Elizabeth X.; Ikejiri, Elza S.; Mamone, Maria Conceição; Paiva, Elias R.; Maciel, Rui M.B.; Furlanetto, Reinaldo P.
2003-10-01

Resumo em português A injeção percutânea de etanol (IPE) guiada por ultra-som tem sido utilizada para o tratamento de nódulos tiroidianos autônomos, sólidos e císticos. Apresentamos nossa experiência em 50 pacientes tratados, sendo 26 portadores de nódulos sólidos, 17 de nódulos císticos e 7 de nódulos autônomos (NA). Avaliamos os pacientes 1 semana, 1 mês, 3 meses, 6 meses e 1 ano após a IPE. Após 1 ano, os nódulos sólidos reduziram a 74% do volume inicial, os císticos d (mais) iminuíram 92% sem apresentar recidivas. Um ano após o tratamento dos nódulos autônomos, 5 pacientes estavam em eutiroidismo clínico e laboratorial e 2 em eutiroidismo mas com TSH subnormal. Não houve recorrência da tirotoxicose e a redução nodular foi de 66%. O procedimento foi bem tolerado por todos. Os resultados confirmam que a IPE é uma boa alternativa terapêutica para redução dos nódulos tiroidianos císticos e sólidos e no tratamento dos nódulos autônomos. Resumo em inglês Percutaneous ethanol injection (PEI) guided by ultrasound has been used for the treatment of cystic, solid and autonomous thyroid nodules. We present our experience in the treatment of 50 patients with thyroid nodules: 26 solid, 17 cystic and 7 autonomous (AN). Patients were evaluated 1 week, 1, 3, and 6 months and 1 year after PEI. After one year, solid nodules showed a mean 74% volume reduction, and cysts a volume reduction of 92%, with no recurrences. After one year, 5 (mais) patients with AN reached clinical and laboratory euthyroidism; the other 2 also became euthyroid, but with subnormal TSH. Recurrence of thyrotoxicosis was not observed and mean nodular reduction was 66%. The procedure was well tolerated by all patients. The results confirm that PEI is a good therapeutic alternative for reduction of solid and cystic thyroid nodules and for the treatment of autonomous nodules.

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11

Eletroxidação do etanol em eletrodos de Ti/IrO2/ Electro-oxidation of ethanol in Ti/IrO2

Fidelis, Carlos H.V.; Donate, Paulo M.; Andrade, Adalgisa R. de
2001-02-01

Resumo em inglês It has been carried out an investigation of ethanol electro-oxidation on Ti/IrO2 electrodes. The experimental results show a high selectivity towards acetaldehyde formation thus, offering potential advantages in cost and availability of raw material. It has been observed that the electrode is partially blocked by a film formed after the oxidation of the starting material which can be removed by pulse technique between RDO and RDH onset. The mechanism and the selectivity of the product formed is presented.

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12

Estudo da oxidação total do etanol usando óxidos tipo perovskita LaBO3 (B= Mn, Ni, Fe)/ Study of total oxidation of ethanol using the perovskite-type oxides LaBO3 (B= Mn, Ni, Fe)

Soares, Ana Brígida; Silva, Paulo Roberto Nagipe da; Freitas, Jair C. C.; Almeida, Clara Muniz de
2007-10-01

Resumo em inglês The present work investigated the effect of coprecipitation-oxidant synthesis on the specific surface area of perovskite-type oxides LaBO3 (B= Mn, Ni, Fe) for total oxidation of ethanol. The perovskite-type oxides were characterized by X-ray diffraction, nitrogen adsorption (BET method), thermogravimetric analysis (TGA-DTA), TPR and X-ray photoelectron spectroscopy (XPS). Through method involving the coprecipitation-oxidant was possible to obtain catalysts with different (mais) BET specific surface areas, of 33-51 m²/g. The results of the catalytic test confirmed that all oxides investigated in this work have specific catalytic activity for total oxidation of ethanol, though the temperatures for total conversion change for each transition metal.

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13

Influência de diferentes sistemas de solvente água-etanol sobre as propriedades físico-químicas e espectroscópicas dos compostos macrocíclicos feofitina e clorofila α/ Influence of different water-ethanol solvent systems on the spectroscopic and physico-chemical properties of the macrocyclic compounds pheophytin and chlorophyll α

Moreira, Leonardo M.; Rodrigues, Máira R.; Oliveira, Hueder P. M. de; Lima, Adriana; Soares, Rafael R. S.; Batistela, Vagner R.; Gerola, Adriana P.; Hioka, Noboru; Severino, Divinomar; Baptista, Mauricio S.; Machado, Antônio Eduardo da Hora
2010-01-01

Resumo em inglês This work focus on the influence of solvent on the photophysical properties of chlorophyll α and pheophytin. Both compounds are related to the photosynthesis process and are considered prototypes of photosensitizers in Photodynamic Therapy. Fluorescence measurements were developed using water/ethanol mixtures at different compositions, since both solvents could be employed in biological applications. The spectroscopic properties of these compounds undergo profound ch (mais) anges depending on water content in the ethanol due to auto-aggregation processes. The major hydrophobicity and the lower dielectric constant of ethanol when compared with water precluded significantly the auto-aggregation process of these compounds.

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14

O efeito do consumo crônico de etanol na absorção duodenal de ferro em camundongos/ The effect of chronic ethanol consumption on duodenal absorption of iron in mice

Sabino, Kelly Renata; Petroianu, Andy; Alberti, Luiz Ronaldo; Machado, Adriana Nunes
2010-06-01

Resumo em português CONTEXTO: Os indivíduos alcoolistas apresentam aumento da concentração hepática de ferro e os mecanismos responsáveis por essa deposição são ainda desconhecidos. Apesar da extensa literatura existente sobre a absorção de ferro nos diferentes estados patológicos, os efeitos do consumo prolongado do etanol não estão totalmente esclarecidos. OBJETIVOS: Determinar a absorção de ferro no duodeno de camundongos após consumo prolongado de etanol, com relação ao (mais) controle de camundongos normais. MÉTODOS: Foram utilizados 10 camundongos machos da raça Swiss, distribuídos em dois grupos: grupo 1 (n = 5) - controle e grupo 2 (n = 5) - consumo de água com etanol, como única fonte de água ofertada. Os animais foram acompanhados durante 120 dias. Decorrido esse período, isolou-se o duodeno e pela parte oral de cada alça, infundiu-se solução salina contendo ascorbato de ferro II na concentração de 0,016 mg de ferro elemento. O efluente foi coletado nos tempos 20, 40, 60, 80, 100 e 120 minutos. Os resultados foram analisados pelo teste Mann-Whitney e Kruskal-Wallis, com significância para P Resumo em inglês CONTEXT: Alcoholists present an increase of iron hepatic concentration, although the responsible mechanisms for this deposition are still unknown. Despite the extensive literature related on the iron absorption in different pathological conditions, the effect of chronic ethanol consumption are still not conclusive and not completely understood. OBJECTIVE: To verify the effect of chronic ethanol ingestion on duodenal absorption of iron. METHODS: Ten male Swiss mice were di (mais) vided into two groups: group 1 (n = 5) - control, and group 2 (n = 5) - water consumption with ethanol, as only water source. The animals were followed during 120 days. After this period, the duodenum was isolated and saline solution containing ascorbate of iron II in the 0,016 concentration of mg of iron element was infused. The effluent was collected in times 20, 40, 60, 80, 100 and 120 minutes. The results were analyzed by Mann-Whitney and Kruskal-Wallis tests. The significance was set for P

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15

Efeito da injeção percutânea de etanol na redução de nódulos tireoideanos/ Percutaneous ethanol injection for the treatment of thyroid nodules

Alcântara-Jones, Daysi M. de; Araújo, Leila Maria Batista; Almeida, Alessandro de M.; Jones, Daniel de Alcântara; Cardoso, Lázaro José Góes; Passos, Marize Carvalho
2006-02-01

Resumo em português Para verificar a eficácia da injeção percutânea de etanol (IPE) no tratamento de nódulos tireoideanos (NT) comparou-se o volume de 86 nódulos (77 pacientes), antes e após uma ou duas sessões de alcoolização. As medianas do volume inicial e final foram respectivamente: 3,5 mL (0,3 a 82,7) e 1,8 mL (0 a 29,4). Sete por cento dos nódulos desapareceram e a média de redução volumétrica foi de 52,6% ± 31,1 (p(mais) ficos responderam distintamente ao tratamento, com as seguintes medianas de redução: 37,3% (variando de -39,0 a 82,6) nos NT sólidos; 53,5% (14,6 a 88,0) nos predominantemente sólidos; 58,0% (21,0 a 64,5) nos mistos; 71,0% (18,8 a 100,0) nos predominantemente císticos e 90,9% (45,9 a 100,0) nos císticos. Adicionalmente, buscou-se comparar a variação do maior diâmetro dos NT, inicialmente sem tratamento, e após a alcoolização, cuja diferença foi estatisticamente significante (p Resumo em inglês To verify the effectiveness of percutaneous ethanol injection (PEI) in the treatment of thyroid nodules (TN), we analyzed 86 TN from 77 patients before and after one or two sessions of PEI. The medians of the initial and final volumes were: 3.5 mL (range 0.3 ­ 82.7) and 1.8 mL (range 0 ­ 29.4). Seven percent of the nodules disappeared and the mean nodule size reduction was 52.6% (p(mais) 9.0 ­ 82.6) for solid; 53.5% (14.6 ­ 88.0) for mostly solid; 58.0% (21.0 ­ 64.5) for mixed; 71.0% (18.8 ­ 100.0) for mostly cystic and 90.0% (45.9 ­ 100.0) for cystic lesions. Furthermore, we compared the variation of the greatest diameter of TN, without any treatment and after PEI, and found this difference statistically significant (p

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16

Efeitos da exposição pré-natal e pós-natal ao etanol no córtex cerebral de ratos: um estudo do neurópilo/ Effects of prenatal and postnatal ethanol exposure in the cerebral cortex of rats: a study of neuropil

Jerônimo, Márcio Sousa; Pontes Filho, Nicodemos Teles de; Melo Júnior, Mário Ribeiro de
2008-02-01

Resumo em português INTRODUÇÃO: Exposição pré-natal ao etanol é freqüentemente associada a microcefalia e atraso na migração celular. O mecanismo pelo qual o etanol induz seus efeitos no desenvolvimento do sistema nervoso não é muito bem entendido. OBJETIVOS: Avaliar o efeito da exposição crônica ao etanol sobre o córtex visual de ratos durante seu desenvolvimento. MATERIAL E MÉTODO: Ratos Wistar provenientes do acasalamento de 30 fêmeas, divididos nos grupos etanol (n = 10) (mais) - 3 g/kg/dia - e controle (n = 10), foram utilizados nesse experimento. Os ratos foram perfundidos e o encéfalo, dividido em três partes: anterior, médio e posterior. Os cortes obtidos do fragmento posterior foram expostos à rotina histológica e submetidos a diferentes técnicas de coloração. Na análise estatística foi utilizado o teste t para comparar os pesos encefálicos e corporais. Considerou-se como nível de rejeição de hipótese nula um valor de p Resumo em inglês BACKGROUND: Prenatal exposure to ethanol is frequently associated with microencephaly and delayed cell migration. The mechanism by which ethanol affects the development of the nervous system is still not fully understood. OBJECTIVE: To evaluate the effect of chronic exposure to ethanol on the visual cortex of rats during their development. MATERIAL AND METHOD: Wistar rats, born from the mating of 30 females, were divided into two groups: those exposed to ethanol (n = 10) (mais) - 3 g/kg/day - and a control group (n = 10). The rats were perfused and brain was divided into three parts: anterior, middle and posterior. Slices taken from the posterior fragment were subjected to histological analysis routine and different staining techniques. A statistical analysis was carried out using t test to compare brain and body weight. A value

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17

Desenvolvimento de um equipamento para avaliação do efeito do etanol na pressão de vapor e entalpia de vaporização em gasolinas automotivas/ Development of a device to valuate the effect of ethanol on the vapor pressure and vaporization enthalpy of fuel gasolines

Cataluña, Renato; Silva, Rosângela
2006-06-01

Resumo em inglês The quality of the gasoline utilized for fueling internal combustion engines with spark ignition is directly affected by the gasoline's properties. Thus, the fuel's properties must be in perfect equilibrium to allow the engine to perform optimally, not only insofar as fuel consumption is concerned, but also in order to reduce the emission of pollutants. Vapor pressure and vaporization enthalpy are important properties of a gasoline determining the fuel's behavior under di (mais) fferent operating conditions in internal combustion engines. The study reported here involved the development of a device to determine the vapor pressure and the vaporization enthalpy of formulations containing volumes of 5, 15 and 25% of ethanol in four base gasolines (G1, G2, G3 and G4). The chemical composition of these gasolines was determined using a gas chromatographer equipped with a flame ionization detector (FID).

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18

Produção de hidrogênio a partir da reforma a vapor de etanol utilizando catalisadores Cu/Ni/gama-Al2o3/ Hydrogen production by ethanol steam reforming using Cu/Ni/gamma-Al2o3 catalysts

Maia, Thaísa A.; Bellido, Jorge D. A.; Assaf, Elisabete M.; Assaf, José M.
2007-04-01

Resumo em inglês Cu/Ni/gamma-Al2O3 catalysts were prepared by an impregnation method with 2.5 or 5% wt of copper and 5 or 15% wt of nickel and applied in ethanol steam reforming. The catalysts were characterized by atomic absorption spectrophotometry, X-ray diffraction, temperature programmed reduction with hydrogen and nitrogen adsorption. The samples showed low crystallinity, with the presence of CuO and NiO, both as crystallites and in dispersed phase, as well as of NiO-Al2O3. The cata (mais) lytic tests carried out at 400 ºC, with a 3:1 water/ethanol molar ratio, indicated the 5Cu/5Ni/Al2O3 catalyst as the most active for hydrogen production, with a hydrogen yield of 77% and ethanol conversion of 98%.

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19

Fontes, reatividade e quantificação de metanol e etanol na atmosfera/ Sources, reactivity and quantification of atmospheric methanol and ethanol

Pereira, Pedro Afonso de Paula; Andrade, Jailson B. de
1998-11-01

Resumo em inglês In the last two decades, the use of oxygenated fuels, like methanol and ethanol, pure or in mixture with gasoline, has been growing due to benefits introduced into the air quality. In Brasil, the fraction of light duty vehicles powered by pure hydrated ethanol is estimated at about 4 million, while the remaining vehicles actually utilize a mixture (22:78 v/v) of ethanol:gasoline. As a consequence, there's a need for the availability of methods that can provide the evaluat (mais) ion of possible impacts of alcohol emissions in the formation of chemical species in the atmosphere, as ozone, aldehydes, carboxylic acids and so on. In this paper, methanol and ethanol are discussed in their general aspects, as well as their atmospheric sources, chemical reactivity and available methods of analysis.

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Situação atual e perspectivas do etanol/ The current situation and prospects for ethanol

Macedo, Isaias C.
2007-04-01

Resumo em português Nos últimos trinta anos, a produção de etanol da cana-de-açúcar no Brasil avançou para 17 milhões de metros cúbicos, com perspectivas de atingir 35,7 milhões de metros cúbicos em 2012-2013. Esse crescimento ocorreu com grande aporte de tecnologia, por meio de geração, importação, adaptação e transferência interna. Uma análise das diferentes fases desse desenvolvimento é apresentada, com a evolução dos parâmetros tecnológicos e a grande competitivida (mais) de atingida. A visão atual é que o setor poderá continuar a evoluir com melhorias contínuas ainda de modo importante, mas grandes "saltos" tecnológicos são possíveis mediante o desenvolvimento de tecnologias para o melhor uso da biomassa residual da cana (cerca de dois terços da biomassa total). Os estudos em curso indicam que a contribuição da cana para o suprimento de energia poderá ser muito superior (e diversificada) que a atual, e poderá ocorrer em paralelo com o desenvolvimento de biorrefinarias, levando a produtos de maior valor agregado. Resumo em inglês In the last 30 years, the production of ethanol from sugar cane in Brazil reached 17 million cubic meters and it is expected to achieve 35.7 million cubic meters by 2012-2013. This growth has taken place due to great technological support by means of production, imports, adaptations and internal transferences. An analysis of the different phases of this development, with the evolution of its technological parameters and the great competition of the sector, is presented in (mais) the article. Nowadays, foresights state that the sector may keep evolving with continuous improvements, but sudden technological boosts are also possible through the development of technologies directed towards a better use of the residual biomass of sugar cane (which represents about two thirds of the total biomass). Studies in progress indicate that the sugar cane contribution to energy supply may be superior and more diversified than the current one. They also affirm that this may happen together with bio-refinery development, which will result in products of higher aggregate values.

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Comportamento da atomização eletrotérmica de ouro, prata, bismuto, cádmio, chumbo e estanho em soluções aquosas e em etanol, a partir de diferentes superfícies atomizadoras/ Behavior of electrothermal atomization of gold, silver, bismuth, cadmium, lead, and tin in aqueous solutions and in ethanol starting from different atomizing surfaces

Silva, José Bento Borba da
2004-08-01

Resumo em inglês The atomization behavior of Au, Ag, Bi, Cd, Pb, and Sn from pyrolitic graphite coating (L'vov platform) with the use Pd and Mg solutions, and zirconium coated platform with the analytes in nitric acid 0.2% v/v and in ethanol was investigated. In ethanol medium, the sensitivity gain was three-fold for Bi and Cd using Zr as modifier. Without modifier, the ethanol medium is appropriate only for Au and Cd. In nitric acid medium, the Zr coated platform elevates sensitivity at (mais) least two-fold for Bi and Cd. The method was applied to the determination of Ag, Au and Bi of certified steel samples, after on-line preconcentration, sorption on a minicolumn filled with C-18 bonded to silica gel and elution with ethanol. The concentrations obtained agreed with the recommended values.

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Biorremediação de águas subterrâneas impactadas por gasolina e etanol com o uso de nitrato/ Nitrate bioremediation of groundwater impacted with gasoline and ethanol

Costa, Ana Hilda Romero; Nunes, Cristina Cardoso; Corseuil, Henry Xavier
2009-06-01

Resumo em português Neste estudo, avaliou-se, durante 32 meses e por meio de um experimento de campo, a utilização da biorremediação com injeção de nitrato na recuperação de águas subterrâneas impactadas por gasolina com 25% de etanol. Por meio da análise da massa e da distribuição espacial dos compostos dissolvidos, verificou-se que a bioestimulação influenciou positivamente na biodegradação do etanol e dos BTEX, evitou a formação de zonas altamente redutoras (90% dos val (mais) ores foram superiores a +100 mV) e impediu o avanço das plumas de BTEX e etanol na área monitorada. Os resultados indicam que a bioestimulação com nitrato é uma alternativa altamente eficiente para se remediarem águas subterrâneas impactadas por gasolina contendo etanol. Resumo em inglês In this study, nitrate bioremediation in groundwater impacted with gasoline containing 25% ethanol was evaluated during 32 months in a field experiment. By means of mass and spatial distribution analysis of the dissolved compounds, biostimulation was found to have a positive influence on ethanol and BTEX biodegradation, and prevented the formation of highly reducing zones (90% of values were higher than + 100 mV) and BTEX and ethanol plume migration in the monitoring area (mais) . Results indicate that nitrate biostimulation is a highly efficient alternative in remediating groundwater impacted by gasohol.

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Análise da situação da produção de etanol e biodiesel no Brasil

Kohlhepp, Gerd
2010-01-01

Resumo em português Um dos objetivos da política energética é a redução das emissões de CO2. Os biocombustíveis são uma das alternativas para o setor de transportes. O Brasil é o líder na produção de etanol extraído da cana-de-açúcar. Os preconceitos existentes nos Estados Unidos e na Europa com relação à importação do etanol brasileiro não têm fundamento, pois esse produto apresenta o melhor balanço ecológico e não diminui a produção de gêneros alimentícios. Na (mais) produção de biodiesel à base de soja, os preconceitos são, em parte, justificados. Quanto ao etanol, os países industrializados não deveriam usar critérios exagerados à sustentabilidade da produção como pretexto para proteger seus próprios produtores contra a importação de produtos brasileiros com preço mais competidor. Resumo em inglês One of the aims of energy policies is reducing CO2 emissions. In transports bio-fuels are one of the alternatives. Brazil is the world leader in producing ethanol from sugar cane. Prejudice against imports of Brazilian ethanol in US and EU markets is unjustified, as it represents the best ecological balance and does not reduce production of basic food in Brazil. As to biodiesel on the basis of soybeans social and ecological reserves partly are in order. Regarding ethanol (mais) industrialized countries should not use exaggerated criteria as to sustainability of production as pretext for protecting their own producers from imports of cheaper Brazilian bio-fuels.

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comparação entre processos em SHF e em SSF de bagaço de cana-de-açúcar para a produção de etanol por Saccharomyces cerevisiae/ Comparison of SHF and SSF processes from sugar cane bagasse for ethanol production by Saccharomyces cerevisiae

Santos, Julliana Ribeiro Alves dos; Souto-Maior, Ana Maria; Gouveia, Ester Ribeiro; Martín, Carlos
2010-01-01

Resumo em inglês In this work, four different process configurations, including three simultaneous saccharification and fermentation (SSF) schemes and one separate hydrolysis and fermentation (SHF) scheme, were compared, at 8% water-insoluble solids, regarding ethanol production from steam-pretreated and alkali-delignified sugar cane bagasse. Two configurations included a 16 h lasting enzymatic presaccharification prior to SSF, and the third one was a classical SSF without presaccharifica (mais) tion. Cellulose conversion was higher for the delignified bagasse, and higher in SSF experiments than in SHF. The highest cellulose-to-ethanol conversion (around 60% in 24 h) and maximum ethanol volumetric productivities (0.29-0.30 g/L.h) were achieved in the presaccharification-assisted SSF.

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Rendimento térmico e emissões de contaminantes atmosféricos de gasolinas formuladas com etanol, MBTE e TAEE/ Thermal yield and emission of atmospheric contaminants from gasolines formulated with ethanol, MTBE and TAEE

Silva, Rosângela da; Menezes, Eliana Weber de; Cataluña, Renato
2008-01-01

Resumo em inglês The specific consumption and carbon monoxide (CO) and nitrogen oxide (NO) emissions from gasolines formulated with ethanol, methyl tert-butyl ether (MTBE) and tert-amyl ethyl ether (TAEE) were evaluated in the rich, stoichiometric and lean-burn regions during the operation of an Otto-cycle engine. The use of ethanol as an additive presented high specific consumption, while gasoline formulated with TAEE showed low specific consumption with the engine operating under lean-b (mais) urn conditions. The ethers evaluated here presented a low percentage of CO in the rich-burn region when compared with ethanol.

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Estudo da reciclagem de células na produção biológica de etanol/ The study of recycle in the biological production of ethanol

Marques, Tadeu Alcides; Serra, Gil Eduardo
2004-12-01

Resumo em português Nas destilarias de álcool o conteúdo de etanol, na suspensão de levedura reciclada, gira em torno de 2% a 3%. A reciclagem de células é realizada tanto em fermentações em batelada, como nas contínuas. A fermentação alcoólica e a recuperação de células de leveduras foram avaliadas em laboratório. A levedura recuperada, por centrifugação, nos experimentos laboratoriais, foi tratada e novamente inoculada em novo meio fermentativo para avaliar o efeito tóxic (mais) o do etanol e de outros metabólitos nas fermentações subseqüentes. A cepa Saccharomyces cerevisiae IZ-1904 utilizada foi inoculada em meio de melaço diluído contendo 180g L-1 e 310g L-1 de açúcares redutores totais (ART), com três repetições. O tratamento da levedura recuperada constou de dupla centrifugação e ressuspensão em água e vinho. Foram realizadas oito fermentações, a primeira com fermento multiplicado e as demais com a reciclagem de células das fermentações anteriores. O elevado teor de açúcar foi necessário para obtenção da concentração alcoólica desejada no vinho e, assim, conferir inibições e toxicidades detectáveis. Nas fermentações com concentração de etanol menor que 6,4% (v v-1) o efeito tóxico ou inibidor não foi detectado. A inibição pelo etanol e por outros componentes foi detectada sobre as leveduras e os resultados mostraram que a redução dos componentes reciclados com a levedura pode melhorar o processo fermentativo. Resumo em inglês In alcohol distilleries the ethanol content in recycled yeast suspension range from 2% to 3%. Recycling yeast cells is a useful tool to inoculate another fermentation batch or to continuous fermentation. The ethanolic fermentation and yeast recovering were evaluated in laboratory. The yeast suspension recovered from the wine, by centrifugation, was treated before re-inoculation in new fermentation media, to evaluate the ethanol and other metabolites toxic effect influence (mais) s in the next fermentations batch. The Saccharomyces cerevisiae IZ-1904 strain was used to inoculate molasses medium with 180g L-1 and 310g L-1 of total reducing sugars (TRS). The yeasts recovering treatment was made with double centrifugation and yeast suspension in water and wine. Eight sequential batch fermentations were done, each with three replications. The first fermentation with fresh yeast, and others with recycled cells. The high sugar content was necessary to generate elevated ethanol concentration in the wine, and to confer hard fermentation conditions so the effects of any toxic compounds were introduced and more easily detected. In fermentations with less than 6.4% ethanol (v v-1) there was no toxic effect detected. The ethanol and other metabolites inhibition on yeast were detected and the results showed that the reduction of those components from the recycled yeast suspension might optimize the fermentation process. Ethanol production and yeast death rate were affected by the recycling of ethanol.

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Remoção da adstringência de caquis 'Giombo' com subdosagens de etanol/ Astringency removal of 'Giombo' persimmon with ethanol sub-doses

Edagi, Fernando Kazuhiro; Chiou, Diego Garcia; Terra, Felipe de Angelis Monteiro; Sestari, Ivan; Kluge, Ricardo Alfredo
2009-10-01

Resumo em português O objetivo do trabalho foi avaliar a eficácia da aplicação de subdosagens de etanol na remoção da adstringência de caqui 'Giombo'. Além disso, foi avaliada a influência da temperatura e do tempo de exposição ao etanol no processo de destanização dos frutos. Assim, foram testadas diferentes doses de etanol (1,75; 3,5 e 7mL kg-1 ou 0,3 e 0,6mL L-1 de câmara-1), tempos de exposição (6, 12, 24 e 36h) e temperaturas de aplicação dos tratamentos e de armazename (mais) nto após a aplicação (5, 20 e 24°C). A exposição dos frutos à concentração de 1,75mL de etanol, durante 12 horas, foi suficiente para destanizar completamente os frutos. Após a aplicação dos tratamentos, os frutos levaram quatro dias para estarem aptos ao consumo. A refrigeração de caquis 'Giombo', após o tratamento com etanol, não influenciou o posterior processo de polimerização dos taninos solúveis. Resumo em inglês The objective of this research was to evaluate ethanol sub-doses efficacy on the astringency removal of 'Giombo'. Additionally, it was evaluated the influence of temperature and ethanol exposure time on fruit deastringency. Thus, experiments were carried out with different exposition times (6, 12, 24 and 36h) and ethyl alcohol concentrations (1.75; 3.5 e 7mL kg-1 or 0.3 and 0.6mL L-1 of chamber). Fruit exposition to ethanol concentration of 1.75mL during 12 h was sufficie (mais) nt to remove completely the persimmon fruit astringency. After the treatment application, the fruits needed 4 days to become suitable to consumption. The process of tannin polymerization is not influenced by cold storage.

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Extração e fracionamento simultâneo do óleo da castanha-do-Brasil com etanol/ Extraction and simultaneous separation of the Brazil nuts oil with ethanol

Freitas, Suely Pereira; Freitas-Silva, Otniel; Miranda, Iara Conceição de; Coelho, Maria Alice Zarur
2007-08-01

Resumo em português O objetivo deste trabalho foi utilizar o etanol comercial para extração e fracionamento simultâneos das frações lipídicas presentes na castanha-do-Brasil (Bertholletia excelsea H.B.K.). O óleo foi obtido a partir da castanha desidratada e moída. O processo foi conduzido na proporção 4:1 solvente/substrato (v.p-1) em banho termostatizado a 65 °C, sob agitação de 30 rpm. A mistura foi filtrada, resfriada a 10 °C e, a seguir, centrifugada para separação das f (mais) ases: uma fase com consistência de gel (micela rica), contendo 75% de óleo e 25% de etanol, e a outra líquida, contendo 2,4% de óleo e 97,6% de etanol (micela pobre). Pelas características apresentadas, a micela rica tem potencial para ser utilizada no preparo de cremes vegetais como substituto parcial de gorduras hidrogenadas, cujos efeitos biológicos na saúde dos consumidores vêm provocando muitas polêmicas. Além de ser uma alternativa na obtenção de gorduras para a formulação de alimentos mais seguros, a tecnologia proposta poderá ser estendida a diferentes oleaginosas de interesse comercial, eliminando o uso de n-hexano no processamento de óleos e gorduras vegetais. Resumo em inglês In this work, the extraction and simultaneous separation of lipids from Brazil nuts (Bertholletia excelsa H.B.K.) with ethanol were investigated. Brazil nuts were dried and triturated prior to oil extraction. The process was carried out at a rate of 4:1 solvent to substrate (v.w-1). The raw material and ethanol were placed in an erlenmeyer flask and maintained in a temperature-controlled bath at 65 °C and 30 rpm. After 1 hour, the mixture was filtered under a vacuum and (mais) the resultant miscella was maintained at 10 °C and centrifuged for phase separation. A rich miscella containing 75% oil and 25% ethanol was obtained presenting a gel consistency while a poor miscella, containing 2.4% oil and 97.6% ethanol, was liquid. The rich miscella presented an important potential to partially replace hydrogenate fats in the food industry. Scientific studies indicated that the consumption of trans fatty acids promote serious health effects. Furthermore, the proposed technology can be extended to different commercial oleaginous by eliminating the use of n-hexane in vegetable oils extraction.

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Tratamento de nódulos autônomos e císticos da tireóide com injeção intranodular de etanol/ Treatment of autonomous and cystic thyroid nodules with intranodular ethanol injection

BRAGA-BASARIA, MILENA; TRIPPIA, MARCUS ADRIANO; STOLF, ANDERSON RAVY; MESA JR., CLÉO; GRAF, HANS
2002-12-01

Resumo em português O tratamento com injeção intranodular de etanol vem sendo utilizado há uma década como modalidade terapêutica eficaz no manejo de pacientes com nódulos da tireóide. Diversos estudos validaram o papel desta forma de tratamento em nódulos autônomos, císticos e, mais recentemente, nódulos frios benignos. OBJETIVO: Avaliar a efetividade da injeção intranodular de etanol no tratamento de nódulos císticos e autônomos da tireóide. MÉTODOS: 42 pacientes (26 paci (mais) entes com nódulos císticos e 16 com nódulos autônomos da tireóide) foram submetidos a tratamento com aplicação intranodular de etanol a 99%, guiada por ultra-sonografia e acompanhados por um período mínimo de seis meses. RESULTADOS: Não observamos a ocorrência de complicações maiores durante ou após o tratamento, porém, na maioria dos casos, houve queixa de dor de leve a moderada intensidade e/ou desconforto após a aplicação do etanol. A maioria dos nódulos apresentou redução volumétrica significativa. A média de redução obtida para os nódulos autônomos foi de 50,3% e para os nódulos císticos, 69,3%. Não houve diferença significativa entre os valores basais de T3 total, T4 total e TSH em comparação aos valores obtidos seis meses após o tratamento para o grupo de pacientes com nódulos císticos. O grupo de pacientes com nódulos autônomos apresentou redução nos valores séricos de T3 total e T4 total, assim como elevação dos níveis de TSH, confirmando a efetividade do tratamento. CONCLUSÃO: A injeção intranodular de etanol é uma alternativa segura e eficaz no tratamento de nódulos autônomos e císticos da tireóide. Resumo em inglês Intranodular ethanol injection has been used for the past 10 years as an efficient modality for treating patients with thyroid nodules. Several studies have reported the success of this therapy in autonomous and cystic nodules and, more recently, in cold benign nodules. PURPOSE: To evaluate the efficacy of this therapeutic modality on the treatment of autonomous and cystic thyroid nodules. METHODS: 42 patients (26 with cystic and 16 with autonomous nodules) were treated w (mais) ith ultrasound guided intranodular 99% ethanol injection and followed for 6 months. RESULTS: No major complications were observed during or after treatment, however, most of the patients reported slight to moderate pain and/or discomfort after the injection. Most of the nodules showed reduction after the treatment. Autonomous nodules had a mean reduction of 50.3% and cystic nodules of 69.3%. No significant differences in pretreatment serum total T3, total T4 or TSH were observed among the patients in the cystic group. Patients in the autonomous group with hyperfunctioning nodules showed a decrease in serum total T3, total T4 and an increase in serum TSH levels, hence, proving the effectiveness of this therapy. CONCLUSIONS: Intranodular ethanol injection is a safe and efficient treatment for autonomous and cystic nodules of the thyroid.

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Efeito do teor metálico em catalisadores Co/Al2O3 aplicados à reação de reforma a vapor de etanol/ Effect of metal load in Co/Al2o3 catalysts for ethanol steam reforming

Santos, Rudye K. S.; Batista, Marcelo S.; Assaf, Elisabete M.; Assaf, José M.
2005-08-01

Resumo em inglês The development of cobalt catalysts to produce hydrogen from ethanol is the goal of this investigation. Co/Al2O3 catalysts were prepared by impregnation and characterized by atomic absorption, nitrogen adsorption, X-ray diffraction, Raman spectroscopy, temperature programmed reduction and carbon analysis. The catalysts contained Co3O4 oxide and Co3+ and Co2+ species interacting with alumina. The cobalt load affects the crystal size and the crystalline structure and higher (mais) Co loads influence the reaction mechanism, changing the selectivity of the catalysts, decreasing the amount of CO produced and avoiding the formation of products catalyzed by the support. The ethanol conversion was 50-70% with 10-

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Desenvolvimento de protótipo de células a combustível do tipo óxido sólido com reforma direta/ Prototype development of solid oxide fuel cells with direct reformation

Silva, Marcos Aurélio da; Boaventura, Jaime S.; Alencar, Marcelo G. de; Cerqueira, Cláudio P.
2007-01-01

Resumo em português Catalisador a base de níquel e cobalto e suportado em zircônia estabilizada por ítria (YSZ) foi desenvolvido, caracterizado e utilizado para a produção de hidrogênio a partir de etanol. O teor de metal do catalisador foi em torno de 35% em massa, apresentando boa atividade a partir de 400ºC. Esse catalisador foi testado na reforma a vapor do etanol na presença de baixo teor de água, condição semelhante à operação da PaCOS. O catalisador produzido foi utiliza (mais) do como anodo de células a combustível do tipo PaCOS, com protótipo desenvolvido nesse trabalho; as estruturas anodo/eletrólito/catodo (A/E/C) foram caracterizadas por MEV. A PaCOS foi operada com hidrogênio, metano e etanol, mostrando bom desempenho com este último combustível. A mistura de etanol e metano também foi testada, apresentando resultados promissores para a produção de energia elétrica. Resumo em inglês Catalyst based on nickel and cobalt, supported on zirconia stabilized with ytria (YSZ) was developed, characterized and used for the hydrogen production from ethanol. The catalyst had metal contents of c.a. 35% in weight and presented high activity above 400ºC. This catalyst was tested in ethanol steam reform at very low water concentration, condition similar to that of SOFC operation. The developed catalyst was also used as anode of a unitary solid oxide fuel cell (SOFC (mais) ); the SOFC unitary cell was developed and manufactured in this work. The anode/electrolyte/cathode structure was characterized by SEM. The SOFC was operated with hydrogen, methane or ethanol and showed good performance with the latter fuel. The ethanol and methane mixture was also tested and presented very promising results for the production of electrical energy.

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Obtenção e caracterização físico-química de concentrado protéico de folhas de mandioca/ Production and physicochemical characterization of cassava leaf protein concentrate

Teo, Carla R. P. A.; Prudencio, Sandra H.; Coelho, Silvia R. M.; Teo, Mauro S.
2010-09-01

Resumo em português Este trabalho tem, como objetivo, comparar concentrados protéicos de folhas de mandioca produzidos por diferentes métodos e propor procedimento de obtenção com maior rendimento, conteúdo e recuperação protéica, menor teor de taninos e cor mais clara. Concentrados protéicos foram obtidos por coagulação ácida (pH = 5), termocoagulação ácida (pH = 4 e a temepratura 85 e 50 °C), coagulação em 30% etanol e termocoagulação (60 °C). Foram determinados nos co (mais) ncentrados protéicos e nas folhas umidade, proteína, taninos, luminosidade e tonalidade cromática. Os concentrados de maior rendimento, conteúdo protéico e cor mais clara (termocoagulação ácida pH 4 a 50 °C e coagulação 30% etanol) foram modificados. Após as modificações o concentrado obtido por coagulação em etanol apresentou 14,1% de recuperação protéica, luminosidade de 73,8 e tonalidade cromática de 99,8°, não diferindo do concentrado produzido por termocoagulação ácida. O conteúdo de taninos foi de 0,4% nos dois concentrados. Os procedimentos de termocoagulação ácida em pH 4 e 50 °C e coagulação em 30% etanol modificados, são apropriados para a produção de concentrado protéico de folhas de mandioca com grande recuperação protéica e cor clara. Resumo em inglês The aim of this work was to compare cassava leaf protein concentrates produced by different methods and to propose procedures with large yield, protein content and recovery, small tannin content and light color. Protein concentrates were obtained by acid coagulation (pH = 5), acid thermo-coagulation (pH = 4 at 85 and 50 °C), 30% ethanol coagulation and thermo-coagulation (60 °C). Moisture, protein and tannin contents, and brightness and chromatic tonality were determine (mais) d in protein concentrates and dried milled leaves. The concentrates with the largest yields, protein contents and the lightest colors (acid thermo-coagulation pH 4 and 50 °C and 30% ethanol coagulation) were modified and, after the concentrate obtained by ethanol coagulation, presented a 14.1% protein recovery, a 73.8 brightness and 99.8° chromatic tonality, not differing from the one produced by acid thermo-coagulation. The tannin content was 0.4% in both concentrates. The modified acid thermo-coagulation in pH 4 and 50 °C and 30% ethanol coagulation procedures are correct for cassava leaf protein concentrate production with large protein recovery and light color.

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Avaliação da queima e da adição de milho desintegrado com palha e sabugo na ensilagem de cana-de-açúcar/ Effect of burning and addition of dehydrated corn cob and straw on sugar cane silage

Bernardes, Thiago Fernandes; Reis, Ricardo Andrade; Siqueira, Gustavo Rezende; Berchielli, Telma Teresinha; Coan, Rogério Marchiori
2007-04-01

Resumo em português Neste trabalho, avaliou-se a fermentação da cana-de-açúcar queimada, ensilada com ou sem uso de aditivo seco. Os tratamentos (seis no total) consistiram da silagem de cana crua ou queimada, adicionada de 0, 50 ou 100 g/kg de milho desintegrado com palha e sabugo (MDPS), com base no peso verde da forragem. Foram determinados os teores de MS, PB, nitrogênio insolúvel em detergente ácido (NIDA), FDN, FDA, celulose, hemicelulose e lignina. Na avaliação das caracterí (mais) sticas fermentativas, foram determinados os valores de carboidratos solúveis, o poder tamponante, o pH e as concentrações de nitrogênio amoniacal e etanol. Como características microbiológicas, avaliou-se o desenvolvimento de leveduras. A inclusão de MDPS elevou os teores de MS e reduziu discretamente os teores de N-NH3 e etanol das silagens, não ocasionando efeito nos valores de pH e na população de leveduras. A presença do fogo reduziu a concentração de MS das silagens, elevou os teores de etanol e leveduras e diminuiu os teores de N-NH3. A fermentação etanólica durante a ensilagem não foi controlada com a inclusão de aditivo seco ou com o uso do fogo. Resumo em inglês This research aimed to evaluate the effects of burning and the use of dry additive on the sugar cane silage fermentative pattern. Six treatments were tested: natural or burned sugarcane, associated to three supplementation levels: 0, 50 or 100 g/kg of dehydrated corn grain, cob, and straw (CGCS) based on forage fresh mater. The following response variables were determined in the forage: DM, CP, acid detergent insoluble nitrogen (ADIN), NDF, ADF, cellulose, hemicellulose a (mais) nd lignin concentrations. Considering the fermentative traits, soluble carbohydrate levels, buffering capacity, pH, ammonia nitrogen and ethanol levels were measured. The CGCS inclusion increased DM concentration and slightly reduced ethanol and N-NH3 levels in silages, but did not affect pH or yeast growth. Burning reduced DM and N-NH3 concentration, as well as increased ethanol levels and yeast growth. Ethanol production in sugarcane silage was not controlled by using dry additive or burning.

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Alcoolização de nódulo tiroidiano em região endêmica de bócio colóide/ Alcoholization in the treatment of thyroid nodule in colloid goiter endemic region

Lima, Marcus Aurelho; Fagundes, Tales Alvarenga; Raffaelli, Cristiane Mendes; Ferreira, Beatriz Pires; Resende, Elisabete Mantovani; Fonseca, Elvi Cristina Rojas; Borges, Maria de Fátima
2007-08-01

Resumo em português A doença nodular tiroidiana é problema clínico comum, principalmente em regiões com carência de iodo. Esse estudo avaliou a eficácia da injeção percutânea de etanol (IPE) no tratamento de nódulos tiroidianos únicos, múltiplos, sólidos, císticos, de diferentes tamanhos com ou sem disfunção glandular, em região endêmica de bócio. Quarenta e dois pacientes com diagnóstico de bócio colóide ou hiperplasia nodular colóide, na punção biópsia aspirativa (mais) por agulha fina (PBAAF), foram selecionados para análise após terem sido submetidos a pelo menos duas IPEs. Os nódulos tiroidianos eram múltiplos (sólidos e ou císticos) em 52,4% dos pacientes, únicos e sólidos ou mistos em 35,7% e únicos e císticos em 11,9%. A redução média dos nódulos após injeção de etanol foi de 58,2% para os únicos e 60,8% nos císticos. Nos nódulos múltiplos, avaliou-se a redução de todo o lobo tiroidiano, alcançando 52,4% de redução. Os efeitos colaterais registrados foram decorrentes apenas do desconforto na aplicação. Este estudo indica que a injeção percutânea de etanol (IPE), alcançando reduções médias de volume que variam de 49 a 60%, é método seguro, eficaz e simples para o tratamento de nódulos tiroidianos benignos. Resumo em inglês Thyroid nodular disease is a common clinical disorder mainly in iodine lacking regions. This study has evaluated the effectiveness of percutaneous ethanol injection (PEI) in the treatment of single, multiple, solid, and cystic thyroid nodules of different sizes with or without glandular dysfunction, in goiter endemic region. Forty-two patients with diagnosis of colloid goiter or colloid nodular hyperplasia in fine-needle aspiration (FNA) were selected for analysis, after (mais) having been submitted to at least two PEI. Thyroid nodules were multiple (solid and or cystic) in 52.4% of the patients, single and solid or mixed in 35.7%, and single and cystic in 11.9%. The mean reduction of nodules after ethanol injection was of 58.2% in the single and of 60.8% in the cystic ones. The reduction of the whole thyroid lobe was evaluated in the multiple nodules and it reached 52.4%. The side-effects were registered only as a consequence of the application discomfort. This study points out that the percutaneous ethanol injection reaching volume mean reductions, varying from 49% to 60%, is a safe, effective, and simple method for the treatment of benign thyroid nodules.

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Características da silagem de cana-de-açúcar tratada com inoculante bacteriano e hidróxido de sódio e acrescida de resíduo da colheita de soja/ Characteristics of sugarcane silage treated with bacterial inoculant, sodium hydroxide or soybean crop residue

Freitas, Acyr Wanderley de Paula; Pereira, José Carlos; Rocha, Fernanda Cipriano; Detmann, Edenio; Ribeiro, Marinaldo Divino; Costa, Marcone Geraldo; Leonel, Fernando de Paula
2006-02-01

Resumo em português Objetivou-se neste trabalho avaliar a qualidade nutricional e as características fermentativas da silagem de cana-de-açúcar tratada com inoculante microbiano (Lactobacillus plantarum nas doses 1,0; 1,2 e 1,4 x 10(6) ufc/g MN) e hidróxido de sódio (solução 40% na base de 3% da MS) e acrescida de 10% de resíduo da colheita de soja, com base no peso verde da cana. Foi utilizada a variedade RB855536, colhida em soca aos 11 e 13 meses. O experimento foi conduzido em de (mais) lineamento inteiramente ao acaso, com três repetições, em esquema fatorial 2 x 8 (duas idades e oito tratamentos da massa ensilada). Os resultados foram avaliados pela análise de fatores. Para as variáveis de composição e cinética de degradação, foram obtidos três fatores: QN - qualidade nutritiva, incluindo MS, PB, DIVMS, FDN, FDA e LIG; MF - maturidade fisiológica, incluindo carboidratos solúveis, LIG e fração indegradável da FDN; e VDF - velocidade de degradação dos carboidratos fibrosos, contemplando o kdFDN. Às variáveis de características de fermentação atribuíram-se os fatores: PFS - perdas e fermentação secundária, incluindo perda de MS, concentração de ácido acético, ácido propiônico e etanol; PH - potencial hidrogeniônico, pH; e DP - degradação protéica, concentração de nitrogênio amoniacal. O resíduo da colheita da soja na ensilagem da cana-de-açúcar foi capaz de melhorar a qualidade nutritiva e reduzir as perdas de MS e a produção de etanol das silagens. O tratamento com hidróxido de sódio diminuiu a produção de etanol, mas não melhorou a qualidade nutritiva e não reduziu as perdas de MS das silagens. A utilização de inoculante microbiano contendo L. plantarum também não melhorou a qualidade nutritiva da silagem nem reduziu as perdas de MS e a produção de etanol. Resumo em inglês The objective of this trial was to evaluate the nutritional quality and fermentation characteristics of sugarcane silages treated with inoculant (Lactobacillus plantarum in doses of 1.0, 1.2 and 1.4 x 10(6) cfu/g NM), 40% sodium hydroxide solution (3% dry matter basis), or 10% of soybean crop residue added according to the sugarcane fresh weight. The variety RB855536 harvested at 11 and 13 months of age was used. The experiment was conducted at the Universidade Federal de (mais) Viçosa Animal Science Department, Viçosa, MG, in a completely randomized design (three repetitions per treatment) with a factorial arrangement of 2 x 8 (two ages and eight treatments). For evaluation of chemical composition and degradation kinetic of silages three parameters were considered: 1) "nutritional quality" that included contents of dry matter, crude protein, neutral detergent fiber, acid detergent fiber, lignin and in vitro dry matter digestibility; 2) "physiological maturity" that included soluble carbohydrates, lignin, and the neutral detergent fiber undegradable fraction; and 3) "degradation velocity of fiber carbohydrates" that included kdNDF. For evaluation of fermentation characteristics the following parameters were adopted: 1) "secondary fermentation and losses" that included DM losses, acetic acid, propionic acid, and ethanol concentrations; 2) "hydrogen potential" (pH); and 3) "protein degradation" (PD) that included ammonia-N concentration. Soy crop residue improved silage nutritional quality and reduced both DM losses and ethanol production. Treatment with sodium hydroxide also decreased ethanol production but did not improve nutritional quality and was not able to prevent DM losses. Use of L. plantarum did not improve the nutritional quality of silages or reduced their DM losses and ethanol production.

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Efeitos do teor de carboidratos solúveis sobre as características da silagem de cana-de-açúcar/ Effect of water soluble carbohydrates on characteristics of sugarcane silage

Silva, Estela Jorge Alves da; Borgatti, Laura Maria Oliveira; Meyer, Paula Marques; Marino, Carolina Tobias; Rodrigues, Paulo Henrique Mazza
2008-08-01

Resumo em português Objetivou-se quantificar na cana-de-açúcar o teor de carboidratos solúveis (CHOs) que anula a produção de etanol e avaliar os efeitos desses carboidratos sobre o valor nutritivo e outras características fermentativas da silagem de cana-de-açúcar. Utilizou-se o delineamento inteiramente casualizado com três tratamentos, cada um com quatro repetições. Os tratamentos consistiram da retirada total do caldo da cana-de-açúcar, por meio de prensagem, e de sua recons (mais) tituição (0, 50 ou 100%) à cana. No nível de 50% de reconstituição, o caldo foi adicionado à cana juntamente com 50% de água e, no nível 0%, adicionou-se 100% de água à cana. A restituição resultou em concentrações de 41,6; 34,0 e 23,0% de carboidratos solúveis na matéria seca (MS). O material foi ensilado em 12 silos experimentais confeccionados a partir de baldes plásticos. A abertura dos silos foi realizada 85 dias após a ensilagem, quando foram determinados os teores dos ácidos orgânicos e a composição química das silagens. A retirada de carboidratos solúveis da cana-de-açúcar teve efeito linear decrescente sobre os teores de matéria seca, o teor de carboidratos solúveis e a digestibilidade in vitro da matéria seca (DIVMS) das silagens, no entanto, ocasionou aumento dos teores de fibra detergente ácido (FDA), fibra detergente neutro (FDN) e lignina. Observou-se efeito linear decrescente da retirada dos carboidratos solúveis sobre os teores de etanol e ácidos lático e butírico e as perdas de matéria seca das silagens. Não se observaram efeitos de tratamentos sobre os dados de estabilidade aeróbia. A produção de etanol seria nula se a cana-de-açúcar contivesse apenas 12,4% de CHOs com base na matéria seca (MS). Resumo em inglês The objectives of this trial were to quantify the water soluble carbohydrates (WSC) concentration present in sugarcane that nullifies ethanol production, and to evaluate the effects of WSC content on nutritive value and other fermentative characteristics of sugarcane silage. A completely randomized design was used with three treatments and four repetitions per treatment. Sugarcane was squeezed in order to remove juice. In the first treatment, juice was totally added back (mais) to sugarcane (100%). In the second treatment, only 50% of the juice was added back to sugarcane, along with 50% of water. In the third, 100% of water was added, with no addition of juice. Treatments resulted in WSC concentrations of 41.6, 34.0, and 23.0% on dry matter basis. The material was ensiled in 12 laboratory silos (plastic buckets). Silos were opened 85 days after ensiling, when organic acids concentration and chemical composition of silages were determined. Withdrawal of sugarcane WSC resulted in negative linear effects on dry matter, WSC concentration, and in vitro digestibility of dry matter, but with linear increase for acid detergent fiber, neutral detergent fiber, and lignin concentration. Considering the fermentation data, there was linear decrease for dry matter losses, lactic and butyric acids, and ethanol concentration. No treatment effect on aerobic stability data was observed. Ethanol production would be null if sugarcane had only 12.4% of water-soluble carbohydrates on dry matter basis.

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Parâmetros de fermentação de silagens de cana-de-açúcar submetidas a diferentes tratamentos/ Fermentation parameters of sugar cane silages submitted to different treatments

Castro Neto, A.G.; Molina, L.R.; Gonçalves, L.C.; Jayme, C.G.
2008-10-01

Resumo em português Os valores de materia seca (MS), pH, teores de N-NH3/NT, ácidos orgânicos e etanol, de silagens de cana-de-açúcar foram determinados, em delineamento experimental em blocos ao acaso. Os tratamentos aplicados à silagens foram: sem aditivo, testemunha (T); 0,5% de uréia (U); 0,5% de zeólita (Z); 0,5% de uréia mais 0,5% de zeólita (U+Z); inoculante bacteriano/enzimático Bio Max® cana (IBB) e inoculante bacteriano Silobac® (IBS). As silagens foram analisadas aos 5 (mais) 6 dias após ensilagem. Os tratamentos U e U+Z apresentaram concentrações médias de ácido lático mais altas que o T, respectivamente 8,9 e 4,7g%. Os teores de etanol das silagens aditivadas foram semelhantes aos do tratamento T, respectivamente 12,4 e 12,9g%, sugerindo que não houve redução da fermentação alcoólica no material tratado. Com exceção da uréia, nenhum dos outros aditivos utilizados neste experimento promoveu melhoria de parâmetros qualitativos das silagens avaliadas. O efeito benéfico da uréia sobre a qualidade da silagem de cana parece ter sido limitado, não suprimindo a ocorrência do processo de fermentação alcoólica no material. Resumo em inglês The values of dry matter (DM), pH, amoniacal nitrogen/total nitrogen (N-NH3/NT), organic acids, and ethanol of sugar cane silages were determined using a randomized blocks design. The treatment were: no addtitive (control); 0.5% urea (U); 0.5% zeolite (Z); 0.5% urea plus 0.5% zeolite (U+Z); Bio Max® (IBB), and Silobac® (IBS). Silages were analyzed on the 56th day after ensiling. The U and U+Z treatments showed high latic acid concentrations in relation to control, respe (mais) ctively 8.9 and 4.7g%. The average ethanol contents of the treated silages were similar to control, respectively 12.4 and 12.9g%, suggesting no reduction of the alcoholic fermentation process in treated materials. Additives used in this experiment did not enhance the qualitative parameters of the silages except for urea treated silages. It was concluded that the beneficial effect of urea on the quality of the sugar cane silages in the conditions of this experiment is limited, not suppressing the occurrence of the alcoholic fermentation process in the material.

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Biotecnologia e desenvolvimento sustentável

Schenberg, Ana Clara Guerrini
2010-01-01

Resumo em português A biotecnologia pode desempenhar um papel importante para atingir as metas da sustentabilidade. No presente trabalho, são descritos diferentes exemplos bem-sucedidos de micro-organismos especialmente desenhados para otimizar a produção de etanol, a produção de plásticos biodegradáveis a partir de recursos renováveis e a biorremediação de metais tóxicos. Esses processos biotecnológicos contribuem significantemente para promover o desenvolvimento sustentável, e (mais) mbora possam, por enquanto, não ser ainda competitivos em relação às tecnologias convencionais. Resumo em inglês Biotechnology can play an important role to reach the goals of sustainability. In the present work, we describe successful examples of microorganisms especially designed for optimizing ethanol production, biodegradable plastics production from renewable resources, and toxic metals bioremediation. These biotechnological processes significantly contribute to promote sustainable development, although they may, at present, not be competitive with the conventional technologies.

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Propriedades farmacológicas do extrato etanólico de Eremanthus erythropappus (DC.) McLeisch (Asteraceae)/ Pharmacological properties of the ethanol extract from Eremanthus erythropappus (DC.) McLeisch (Asteraceae)

Silvério, Marcelo S.; Sousa, Orlando V.; Del-Vechio-Vieira, Glauciemar; Miranda, Mariza A.; Matheus, Filipe C.; Kaplan, Maria A. C.
2008-09-01

Resumo em português O presente trabalho investigou as propriedades antinociceptiva, antiinflamatória e antiulcerogênica do extrato etanólico dos galhos de E. erythropappus. Foram realizados os testes de contorções abdominais induzidas por ácido acético; tempo da lambida da pata induzida por formalina; placa quente; edema de pata induzido por carragenina; lesões ulcerativas induzidas por indometacina e etanol. As doses de 50, 100 e 200 mg/kg inibiram as contorções em 43,07%, 69,34% (mais) e 70,07%, respectivamente. O tempo da lambida da pata foi reduzido em ambas as fases nas doses testadas, enquanto o tempo de latência da placa quente teve efeito significativo na dose de 200 mg/kg. O edema de pata foi reduzido em 23,81% (100 mg/kg) e 47,62% (200 mg/kg). O índice ulcerativo das lesões induzidas por indometacina foi reduzido na dose de 100 mg/kg e 200 mg/kg, enquanto a dose de 200 mg/kg teve efeito significativo sobre o volume e o pH do suco gástrico. O índice ulcerativo e o volume do suco gástrico, induzidos por etanol, foram reduzidos na dose de 200 mg/kg, enquanto o pH do suco gástrico aumentou nas doses de 100 e 200 mg/kg. Os resultados indicam que o extrato etanólico de E. erythropappus avaliado pode constituir alvo potencial para uso em terapias da dor, da inflamação e de úlcera. Resumo em inglês The present work investigated the antinociceptive, anti-inflammatory and antiulcerogenic activities of Eremanthus erythropappus ethanol extract. The tests were carried out by acetic acid writhing, paw licking induced by formalin, hot plate, indomethacin- and ethanol-induced ulcer. The doses of 50, 100 and 200 mg/kg inhibited the contortions in 43.07, 69.34 and 70.07%, respectively. Both phases of paw lick were reduced at the tested doses, while reaction time at hot plate (mais) had significant effect at 200 mg/kg. The paw edema was decreased in 23.81% (100 mg/kg) and 47.62% (200 mg/kg). The index of ulceration induced by indomethacin was reduced at the doses of 100 and 200 mg/kg, while 200 mg/kg decreased the gastric volume and pH. The index of ulceration and gastric volume induced by ethanol was reduced at 200 mg/kg, while the pH increased at 100 and 200 mg/kg. The results indicate that the ethanol extract from E. erythropappus may constitute a potential target for the use in therapies of the pain, inflammation and ulcer.

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Novos aditivos microbianos na ensilagem da cana-de-açúcar: composição bromatológica, perdas fermentativas, componentes voláteis e estabilidade aeróbia/ New microbial additives on sugarcane ensilage: bromatological composition, fermentative losses, volatile compounds and aerobic stability

Schmidt, Patrick; Rossi Junior, Paulo; Junges, Daniel; Dias, Laila Talarico; Almeida, Rodrigo de; Mari, Lucas José
2011-03-01

Resumo em português Nesta pesquisa, comparou-se a inclusão de aditivo composto por cepas de Lactobacillus brevis + Enterococcus faecium + L. plantarum à inoculação com aditivo comercial contendo cepas de Lactobacillus buchneri e à ensilagem sem aditivos (controle). As silagens foram confeccionadas em silos experimentais e armazenadas por 90 dias antes da abertura do silo. Foram avaliadas a composição bromatológica da cana-de-açúcar antes e após a ensilagem, a composição de ácid (mais) os orgânicos e etanol das silagens, a estabilidade aeróbia e as perdas fermentativas durante o processo de ensilagem. O uso do aditivo composto e do aditivo comercial contendo cepas de Lactobacillus buchneri provocou aumento da produção de efluentes e de gases e da perda total de matéria seca. O teor de ácido lático da silagem aumentou com o uso do aditivo composto, embora esse aditivo também tenha elevado o teor de etanol (18,6% da MS) em relação ao da silagem controle (14,4%). A estabilidade aeróbia da silagem não foi influenciada pelos inoculantes adicionados no processo de ensilagem. Os aditivos aplicados prejudicaram o processo de ensilagem da cana-de-açúcar. Resumo em inglês In this study, the inclusion of Lactobacillus brevis + Enterococcus faecium + L. plantarum was compared to the inoculation with a commercial additive containing strains of Lactobacillus buchneri and to the silage without additives (control). Silages were prepared in experimental silos and stored for 90 days before opening of the silos. It was evaluated chemical composition of sugarcane before and after ensiling process, composition of organic acids and ethanol in the sila (mais) ges, aerobic stability and fermentative losses during the ensiling process. Use of compound additive and commercial additive containing strains of Lactobacillus buchneri increased production of effluents and gas and total dry matter losses. Lactic acid content in the silage increased with the use of compound additive, although this additive had increased content of ethanol (18.6% of DM) compared with the control ensilage (14.4%). Aerobic stability in the silage was not influenced by inoculants added into ensilage process. The additives used have impaired the ensiling process of sugarcane.

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Efeito de aditivo químico e inoculantes microbianos na fermentação e no controle da produção de álcool em silagens de cana-de-açúcar/ Chemical additive and microbial inoculants effects on the fermentation and on the control of the alcohol production in sugarcane silages

Sousa, Daniel de Paula; Mattos, Wilson Roberto Soares; Nussio, Luiz Gustavo; Mari, Lucas José; Ribeiro, José Leonardo; Santos, Matteus Castilho
2008-09-01

Resumo em português Avaliou-se a eficácia de aditivo químico e inoculantes microbianos nas alterações fermentativas que inibem a produção de etanol e diminuem as perdas de matéria seca em silagens de cana-de-açúcar. A ensilagem foi realizada em baldes plásticos de 20 litros (minissilos) adaptados com válvulas tipo Bunsen para eliminação dos gases e dispositivo para coleta de efluentes. Utilizou-se uréia (1% na matéria verde) como aditivo e os inoculantes microbianos Lalsil can (mais) a® contendo a bactéria heterolática Lactobacillus buchneri (cepa NCIMB 40788) na razão de 3,65 × 10(5) ufc/g massa verde (MV) e um inoculante não comercial contendo a combinação de bactérias homo e heteroláticas Pedioccocus pentosassus e Lactobacillus buchneri (1 × 10(6) ufc/g de massa verde). As amostragens foram realizadas após 110 dias de fermentação. A utilização de uréia e principalmente do aditivo Lactobacillus buchneri + Pediococcus foi eficaz em diminuir a produção de etanol (1,30 e 2,75% vs 8,27% na silagem controle), as perdas de matéria seca (47 e 60%) e o consumo de carboidratos solúveis (22 e 56%) e em aumentar a digestibilidade in vitro da matéria seca (14,7 e 12,4%) quando comparados à silagem controle, respectivamente. Apesar dos altos teores de ácido acético em todas as silagens, principalmente nas silagens acrescidas da combinação de bactérias homo e heteroláticas, não foram verificados efeitos dos inoculantes sobre a população de leveduras. Os valores de pH e ácido lático da silagem com uréia foram maiores que os obtidos na silagem controle. As silagens com L. buchneri apresentaram neste estudo maior produção de etanol (11,53% vs 8,27%, silagem controle), o que refletiu em perdas significativas e baixa recuperação de matéria seca, além de baixa digestibilidade pela perda de carboidratos solúveis e pelo acúmulo de FDN, que foram similares aos das silagens sem aditivo. Resumo em inglês The objective of this study was to evaluate chemical additive and microbial inoculants effectiveness on fermentative changes that lead to the inhibition of the ethanol production and reduction of dry matter losses in sugarcane silages. Silos were made in 20 liter plastic buckets provided with a Bunsen type valve that allows gas to escape and a device to collect effluents. The applied additives were urea (1% of fresh forage); microbial additive Lalsil cana®, that has hete (mais) rolactic bacteria Lactobacillus buchneri (NCIMB 40788), 3.65 × 10(5) CFU g-1 of fresh forage, and a non-commercial additive with homolactic bacteria Pedioccocus pentosassus and Lactobacillus buchneri (1 × 10(6) CFU g-1 FM) supplied by Lallemand Inc. (Montreal, Quebec). Sampling occurred after 110 days of fermentation. Urea and mainly the additive Lactobacillus buchneri and Pediococcus were efficient on the reduction of ethanol production (1.30 and 2.75% versus 8.27% in the control treatment), on the reduction of dry matter losses (47 and 60%) and soluble carbohydrates (22 and 56%), and increase in vitro dry matter digestibility (14,7 and 12,3%) when compared to the control silages, respectively. Despite the high values of acetic acid in all silages, mainly in silages inoculated with homo and heterolactic bacteria, it was not verified effects on yeast population. The silage with urea had greater values of pH and lactic acid compared to control silage. Silages with L. buchneri had, in this experiment, the largest ethanol production (11.53% vs 8.27% from control silage), resulting in greater losses and lower dry matter recovery. In addition, these silages also showed lower digestibility because of soluble carbohydrates losses and NDF accumulation, similar to the silages without additive.

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Atividade hepatoprotetora dos extratos etanólico e hexânico das folhas de Momordica charantia/ Hepatoprotective activity of hexane and ethanol extracts from Momordica charantia L. leaves

Pereira, B.S.; Nunes-Pinheiro, D.C.S; Vasconcelos, A.K.P.; Pinheiro, A.D.N; Rodrigues, P.A.
2010-09-01

Resumo em português Momordica charantia L. (Cucurbitaceae) é empregada na medicina popular pelas diversas propriedades biológicas e farmacológicas. Neste trabalho, objetivou-se avaliar a atividade hepatoprotetora dos extratos hexânico (EH) e etanólico (EE) das folhas de M. charantia no modelo de lesão hepática aguda induzida pelo etanol. Em ambos os extratos foram detectados esteróides; EH apresentou atividade antioxidante mais marcante que EE. O pré-tratamento de camundongos (Swiss (mais) , machos) por via oral por três dias consecutivos com 25, 50 ou 100 mg Kg-1 de EH preveniu o aumento tanto de AST quanto de ALT (p Resumo em inglês Momordica charantia L. (Cucurbitaceae) has been used in folk medicine based on its several biological and pharmacological properties. The aim of this work was to evaluate the hepatoprotective activity of hexane (HE) and ethanol (EE) extracts from M. charantia leaves on the acute liver injury model induced by ethanol. Steroids were detected in both extracts, and EH had higher antioxidant activity than EE. Oral pretreatment of male Swiss mice for three consecutive days with (mais) 25, 50 or 100 mg kg-1 HE prevented the increase in AST and ALT (p

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Influência do solvente no conteúdo total de polifenóis, antocianinas e atividade antioxidante de extratos de bagaço de uva (Vitis vinifera) variedades Tannat e Ancelota/ Solvent Influence on total polyphenol content, anthocyanins, and antioxidant activity of grape (Vitis vinifera) bagasse extracts from Tannat and Ancelota - different varieties of Vitis vinifera varieties

Rockenbach, Ismael Ivan; Silva, Graciela Lessa da; Rodrigues, Eliseu; Kuskoski, Eugênia Marta; Fett, Roseane
2008-12-01

Resumo em português Diferentes sistemas solventes foram aplicados para determinar a eficiência de extração de compostos com capacidade antioxidante em bagaço de uva, importante subproduto do processo de vinificação. Realizou-se a quantificação de compostos fenólicos totais, antocianinas totais e atividade antioxidante nos extratos de bagaço de uva Vitis vinifera das variedades Tannat e Ancelota, provenientes da região de Videira, Santa Catarina. A atividade antioxidante foi determ (mais) inada pelos métodos ABTS, FRAP e β-caroteno/ácido linoléico. Conteúdos de compostos fenólicos totais em acetona 50 e 70% foram maiores nas duas variedades, enquanto que os conteúdos de antocianinas totais extraídos em ambas as variedades foram maiores no solvente etanol em concentrações de 50 e 70%. Pelo método ABTS, a atividade antioxidante foi maior nas concentrações de 50 e 70% de acetona para a variedade Tannat e 50 e 70% de acetona e etanol para a variedade Ancelota. Em relação ao poder redutor pelo método FRAP, este foi maior em solvente acetona 70% para as duas variedades. No ensaio do poder de inibição da oxidação, a adição de 100 e 200 µL de extratos etanólicos a 50% das variedades Tannat e Ancelota apresentou maior eficiência, sendo quase duas vezes superior aos extratos acetônicos testados. Resumo em inglês Different solvent systems were applied in order to determine the extraction efficiency of compounds with antioxidant capacity from grape bagasse, an important by-product from wine production. The quantification of total phenolics, anthocyanins, and antioxidant activity was carried out in grape bagasse extracts of Tannat and Ancelota varieties from the region of Videira, state of Santa Catarina. The antioxidant activity was determined by ABTS, FRAP, and β-carotene/lin (mais) oleic acid system methods. Extracts from acidified aqueous solutions of acetone and ethanol in different concentrations (v/v) showed higher yield in aqueous solutions of acetone 50 and 70% for Tannat variety and acetone/ethanol 50% for Ancelota variety, respectively. The total phenolic contents in acetone 50 and 70% were higher in both varieties while the anthocyanin contents in these varieties were higher in ethanol 50 and 70%. The antioxidant activity was higher in acetone 50 and 70% for Tannat variety and acetone/ethanol 50 and 70% for Ancelota variety by the ABTS method. Regarding the reduction power performed by the FRAP method, it was higher in acetone 70% in both varieties. During the oxidation inhibition power assay, the addition of 100 and 200 µL of ethanolic extracts 50% of Tannat and Ancelota varieties showed higher efficiency since it was almost two times higher than acetonic extracts.

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Estudo in vitro da atividade do extrato etanólico de sementes de bacupari (Rheedia gardneriana Planch. & Triana) e das frações no crescimento de Streptococcus mutans/ In vitro study of the activity of ethanol extract from "bacupari" (Rheedia gardneriana Planch. & Triana) seeds and its fractions on Streptococcus mutans growth

Samarão, S.S; Corrêa, L.A.S; Moreira, A.S.N; Freire, M.G.M; Macedo, M.L.R
2010-06-01

Resumo em português Streptococcus mutans, principal microrganismo da cavidade oral, desempenha papel preponderante na formação de placas dentárias, sendo considerado o agente etiológico primário da cárie. Rheedia gardneriana, conhecida popularmente como bacupari, é uma planta utilizada com fins medicinais para o tratamento de diversas patologias, e por apresentar atividade antimicrobiana de compostos das folhas contra bactérias Gram-positivas e Gram-negativas. O objetivo do presente (mais) trabalho foi avaliar o efeito de extrato de semente de R. gardneriana sobre a cepa S. mutans UA159. Os testes foram conduzidos com o extrato etanólico bruto e as frações obtidas com os solventes diclorometano, etanol-água, metanol e hexano, em ensaios de inibição in vitro. O extrato bruto (100%) apresentou halos de inibição com diâmetro similar ao obtido com solução de digluconato de clorexidina 0,12%, usada como controle. Os ensaios com a fração diclorometano exibiram atividade inibitória 35% menor comparado com o controle, enquanto nenhum efeito antimicrobiano foi observado com a fração etanol-água. Contrariamente, os resultados obtidos com as frações hexânica e metanólica demonstraram claramente a atividade antimicrobiana por inibição do crescimento bacteriano. Na fração metanólica a formação de halos de inibição foi similar ao do controle. Estes dados apresentam atividade antimicrobiana de R. gardneriana contra S. mutans. Resumo em inglês Streptococcus mutans, which is the main microorganism of the oral cavity, plays a preponderant role in dental plaque formation and is considered the primary etiologic agent regarding caries. Commonly known as "bacupari", Rheedia gardneriana is a plant used for medicinal purposes in the treatment of several pathologies; besides, its leaves have compounds that present antimicrobial activity against Gram-positive and Gram-negative bacteria. The aim of this work was to evalua (mais) te the effect of R. gardneriana seed extract on S. mutans strain UA159. The tests were carried out with crude ethanol extract and the fractions obtained with the solvents dichloromethane, ethanol-water, methanol, and hexane in in vitro inhibition assays. The crude extract (100%) presented inhibition halos with diameter similar to that obtained by using 0.12% chlorhexidine digluconate solution as control. Assays with the fraction dichloromethane showed an inhibitory activity 35% lower than that of the control, whereas no antimicrobial effect was observed with the ethanol-water fraction. Conversely, the results obtained with the fractions hexane and methanol clearly demonstrated antimicrobial activity by inhibiting the bacterial growth. In the methanol fraction, the formation of inhibition halos was similar to that in the control. These data present antimicrobial activity of R. gardneriana against S. mutans.

Scientific Electronic Library Online (Portuguese)

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A exposição pré-natal ao álcool como fator de risco para comportamentos disfuncionais: o papel do pediatra/ Prenatal alcohol exposure as a risk factor for dysfunctional behaviors: the role of the pediatrician

Momino, Wakana; Sanseverino, Maria Teresa V.; Schüler-Faccini, Lavínia
2008-08-01

Resumo em português OBJETIVO: Ainda que as características clássicas da síndrome fetal alcoólica tenham sido descritas desde 1968, a pesquisa sobre a teratogênese do álcool apenas recentemente demonstrou que o cérebro é o órgão do corpo mais vulnerável aos efeitos da exposição pré-natal ao álcool. No presente artigo, fazemos uma revisão da literatura focalizando principalmente os distúrbios comportamentais relacionados à exposição pré-natal ao álcool. FONTES DOS DADOS: (mais) Foi realizada uma pesquisa com base no PubMed sobre a literatura publicada entre 1968 e 2006, com as palavras-chave etanol, gestação e comportamento. Foram estabelecidos limites a estudos em humanos. SÍNTESE DOS DADOS: Os dados apresentados nesta revisão sugerem que jovens com efeitos do espectro do álcool fetal estão sob risco maior de terem comportamento social disruptivo, entre outros problemas neurocomportamentais. CONCLUSÕES: Ainda que seja impossível separar completamente a teratogênese sobre o cérebro decorrente da exposição ao álcool de influências ambientais pós-natais como a causa definitiva desses resultados, o pediatra deve ser estimulado ao diagnóstico precoce de crianças afetadas pela síndrome fetal alcoólica e efeitos do espectro do álcool fetal. Isso permite iniciar o manejo e cuidados apropriados para evitar as conseqüências em longo prazo no comportamento e assegurar uma adaptação social e escolar melhor e mais produtiva. Resumo em inglês OBJECTIVE: Although the classic features of fetal alcohol syndrome have been recognized since 1968, research on alcohol teratogenesis has only recently demonstrated that the brain is the organ in the body most vulnerable to the effects of prenatal alcohol exposure. In this present article, we reviewed the literature focusing mainly on behavioral disturbances related to prenatal ethanol exposure. SOURCES: We performed a PubMed search on the literature published between 196 (mais) 8 and 2006 using the terms ethanol, pregnancy and behavior. We limited our search to studies on humans. SUMMARY OF THE FINDINGS: The data presented in this review suggested that youths with fetal alcohol spectrum disorder are at risk of disruptive social behavior, among other neurobehavioral abnormalities. CONCLUSIONS: Although it is still impossible to completely separate brain teratogenesis secondary to alcohol exposure from environmental postnatal influences as the definite cause for these outcomes, the pediatrician should be encouraged to early diagnose children affected by fetal alcohol syndrome and fetal alcohol spectrum disorder. This provides proper management and care and avoids long-term consequences on their behavior, besides ensuring better and productive school and social adaptation.

Scientific Electronic Library Online (Portuguese)

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Atividade antibacteriana in vitro de extratos de alho nirá (Allium tuberosum Rottler ex Spreng.)/ In vitro antibacterial activity of "Nira" garlic extracts (Allium tuberosum Rottler ex-Spreng.)

Araújo, C.A.; Carvalho, H.H.C.; Souto, S.A.; Sobreiro, A.A.; Wiest, J.M.
2009-01-01

Resumo em português Com o objetivo de demonstrar a influência da condimentação sobre a Validade Preditiva dos Resultados Negativos do diagnóstico de bactérias transmissíveis por alimentos, determinou-se, in vitro, a intensidade de atividade de inibição bacteriana (IINIB) e a intensidade de atividade de inativação bacteriana (IINAB) de três acessos de Allium tuberosum Rottler ex Spreng. - Liliaceae - alho "nirá", originários da região metropolitana de Porto Alegre, Rio Grande do (mais) Sul. O extrato etanólico à 50% destes diferentes acessos (alcoolaturas com evaporação do etanol em sistema rotavapor com reconstituição hídrica sob assepsia) foi testado, através de testes de diluição em sistema de tubos múltiplos, sobre inóculos padronizados de Staphylococcus aureus (ATCC 25.923), Enterococcus faecalis (ATCC 19.433), Salmonella enteritidis (ATCC 11.076), Escherichia coli (ATCC 11.229). Os testes revelaram atividade antibacteriana seletiva sobre os diferentes inóculos Gram-negativos, que atingiram inibição e inativação máximas e permanentes para Salmonella após 48 horas, e, para Escherichia coli, após 72 horas de exposição. As bactérias Gram-positivas, Staphylococcus e Enterococcus, apresentaram resistência total frente aos extratos etanólicos Não houve diferença significativa entre si quanto aos tempos de atuação, quanto a Salmonella e Escherichia, quanto à presença ou ausência de desinibidores bacterianos, havendo, entretanto, diferença significativa entre os acessos de alho nirá. Resumo em inglês To demonstrate the influence of seasoning on the Predictive Validity of Negative Results in the diagnosis of bacteria transmissible through food, the intensity of bacterial inhibition activity (IINIB) and the intensity of bacterial inactivation activity (IINAB) were determined in vitro for three sources of Allium tuberosum Rottler ex Spreng. - Liliaceae ("Nira" Garlic) from the metropolitan area of Porto Alegre, Rio Grande do Sul State, Brazil. The 50% ethanol extract of (mais) those different sources (alcoholature obtained with the evaporation of ethanol in rotavapor system with aseptic hydric-reconstitution) was assessed through dilution tests in multiple tube series against standardized inocula of Staphylococcus aureus (ATCC 25923), Enterococcus faecalis (ATCC 19.433), Salmonella enteritidis (ATCC 11.076) and Escherichia coli (ATCC 11.229). Tests revealed selective antibacterial activity against the different Gram-negative inocula, which reached maximum and permanent inhibition and inactivation for Salmonella after 48 hours and for Escherichia coli after 72 hours of exposition. The Gram-negative bacteria, Staphylococcus and Enterococcus, presented total resistance to the ethanol extracts. There were no significant differences among activity times for Salmonella and Escherichia, as well as between presence and absence of bacterial non-inhibitors. However, there were significant differences among "Nira" garlic sources.

Scientific Electronic Library Online (Portuguese)

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Análise morfométrica e ultra-estrutural do nervo óptico de ratos induzidos a ingestão de álcool/ Morphometric and ultrastructural analysis of the optic nerve in rats following induced ethanol consumption

Shiguematsu, Alvio Isao; Schellini, Silvana Artioli; Gregório, Elisa Aparecida; Pellizzon, Cláudia Helena; Müller, Sérgio Swann; Padovani, Carlos Roberto
2003-06-01

Resumo em português OBJETIVO: Analisar os efeitos da ingestão crônica de álcool sobre o nervo óptico em um modelo murino adulto. MÉTODOS: Doze ratos machos da raça Wistar, de 30 dias de idade, foram divididos por sorteio em 2 grupos experimentais: "tratado" (TG), com 8 animais, alimentados com ração-padrão para roedores de laboratório e uma mistura de água de torneira e etanol ad libitum; "controle" (CG), com 4 animais, alimentados com a mesma ração e água de torneira pura ad l (mais) ibitum. Após 40 semanas todos os ratos foram sacrificados, sendo os nervos ópticos de ambos os olhos preparados para microscopia óptica e eletrônica. A área de secção transversal de cada nervo a aumento de 500´, assim como número de fibras axonais dentro de 5 campos aleatoriamente selecionados a aumento de 2000´ foram medidos com auxílio de digitalizador de imagens acoplado ao microscópio óptico. Foram realizadas fotomicrografias de 10 campos aleatoriamente selecionados de cada nervo (5 centrais e 5 periféricos) a aumento de 4200´ em microscópio eletrônico de transmissão. RESULTADOS: A análise morfométrica não mostrou diferenças estatisticamente significativas entre os 2 grupos estudados. Em contraste com o CG, o exame ultra-estrutural dos nervos ópticos do TG mostrou um intenso desarranjo das bainhas de mielina, que se tornaram espessadas, com separação de suas lamelas, apresentando, por vezes, degenerações interlamelares elétron-densas, além da presença de muitas organelas degeneradas. CONCLUSÃO: Os achados desse estudo mostram alterações ultra-estruturais no nervo óptico de ratos adultos após ingestão crônica de álcool, sem modificações morfométricas significativas. Resumo em inglês PURPOSE: To analyze the effects of chronic ethanol intake on the optic nerve in an adult rat model. METHODS: Twelve male, 30-day-old Wistar rats were randomly divided into 2 experimental groups: "treated" (TG), with 8 animals, fed standard laboratory rodent chow and a mixture of tap water and ethanol ad libitum; and "control" (CG), with 4 animals, fed the same chow and pure tap water ad libitum. After 40 weeks all rats were sacrificed, having their optic nerves prepared f (mais) or both licht and electron microscopy. The cross-sectional area of each nerve, at a magnification of ´500, as well as the number of axons within 5 randomized field areas, at a magnification of ´2000, were measured by using an image digitizer. Randomized sampling was made for taking 10 photomicrographs of each nerve (5 central and 5 peripheral) at a magnification of ´4200 in a transmission electron microscope. RESULTS: Morphometric analysis showed no significant differences between both groups. In contrast with CG, the ultrastructural examination of TG optic nerves showed severe disarrangement of myelin sheaths, which became thicker, with separation of their lamellae, presenting sometimes electron-dense degenerations between them, and also many degenerated organellae. CONCLUSION: Our findings show ultrastructural alterations in the optic nerve of adult rats following chronic ethanol consumption, without morphometric changes.

Scientific Electronic Library Online (Portuguese)

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Validação de métodos para determinação de fluoxetina em cápsulas/ Validation of methods for determination of fluoxetine capsules

Fregonezi-Nery, Marlene Maria; Baracat, Marcela Maria; Casagrande, Rubia; Machado, Hodnei Takashi; Miglioranza, Bruna; Gianotto, Elisabeth Aparecida dos Santos; Dalmas, José Carlos
2008-01-01

Resumo em inglês A UV spectrophotometric method was developed and validated and a chromatographic method was adapted from the American Pharmacopeia for the analysis of Fluoxetine Hydrochloride capsules. Ethanol was used as solvent for the spectrophotometric method, with detection and determination at 276 nm. The separation for the chromatographic method was carried out using the reversed-phase column LC-8, triethylamine buffer, stabilizer free tetrahydrofuran and methanol (5:3.5:1.5), pH (mais) 6.0 as mobile phase and detection at 227 nm. The results obtained for both methods showed to be accurate, precise, robust and linear over the concentration range 100.00 - 300.00 µg/mL and 40.00 - 80.00 µg/mL of fluoxetine hydrochloride for the spectrophotometric and chromatographic methods, respectively. The accuracy of the methods was evaluated by a recovery test and showed results between 98.89 and 101.10%.

Scientific Electronic Library Online (Portuguese)

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Validação de método analítico para determinar a migração de ε-caprolactama das embalagens para alimentos gordurosos/ Validation of analytical method to determine ε-caprolactam migration from packagings to fatty food

Bomfim, Marcus Vinicius Justo; Abrantes, Shirley de Mello Pereira; Zamith, Helena Pereira da Silva
2010-01-01

Resumo em inglês ε-Caprolactam (CAP) is a monomer of nylon 6 used as food packaging for bologna sausage, turkey blanquettes, fowl breast, pâtés and ham luncheon meat. After polymerization a part of the monomer can remain in the packaging and migrate into the food. The aim of this work was develop and validate a single laboratory method to determine CAP in ethanol 95% that simulates fatty food characteristics. Thus, linear range was 2 to 32 mg/L of CAP, detection and quantification (mais) limits were 0.83 and 1.63 mg/L, respectively. Repeatability showed Hor Rat values lower than 2 while recovery range was 97.5 to 106.5%. The method was considered adequate for purpose.

Scientific Electronic Library Online (Portuguese)

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Uso da análise exploratória de dados na avaliação de modificadores químicos para determinação direta e simultânea de metais em álcool combustível por GFAAS/ The use of the exploratory analysis in the evaluation of chemical modifiers for direct and simultaneous determination of metals in fuel ethanol by GFAAS

Oliveira, A. P. de; Gomes Neto, J. A.; Ferreira, M. M. C.
2006-01-01

Resumo em português O objetivo deste trabalho foi empregar a análise exploratória de dados, no caso, a técnica de análise de componentes principais (PCA) como ferramenta na avaliação de modificadores químicos na determinação direta e simultânea de Al, As, Cu, Fe, Mn e Ni em álcool etílico combustível por espectrometria de absorção atômica em forno de grafite (GFAAS). Os modificadores químicos avaliados foram: Pd(NO3)2 + Mg(NO3)2; W/Rh; W+ co-injeção de Pd(NO3)2 + Mg(NO3)2 (mais) e para cada modificador foram utilizadas trintas amostras de álcool etílico combustível. Como dados experimentais foram utilizados os resultados dos testes de adição e recuperação dos analitos frente aos diferentes modificadores químicos estudados. O emprego da técnica de PCA possibilitou a separação dos tipos de modificadores em função do intervalo de recuperação do analito. Dentre os modificadores avaliados, W+ co-injeção de Pd(NO3)2 + Mg(NO3)2 apresentou-se como a espécie de maior correlação positiva, pois apresenta os maiores teores de recuperação, e sendo assim, foi o escolhido para o desenvolvimento de metodologia para determinação direta e simultânea de Al, As, Cu, Fe, Mn e Ni em álcool etílico combustível por GFAAS. Resumo em inglês The aim of this work was to employ the exploratory analysis, in this case, the principal component analysis (PCA) as an alternative tool in the evaluation of chemical modifiers for direct and simultaneous determination of Al, As, Cu, Fe, Mn and Ni in ethanol fuel by graphite furnace atomic absorption spectrometry (GFAAS). The evaluated chemical modifiers were Pd(NO3)2 + Mg(NO3)2; W/Rh; W+ co-injection of Pd(NO3)2 + Mg(NO3)2 and 30 samples of ethanol fuel were used for eac (mais) h one. As experimental data were used the results of the addition and recovery tests. The use of the principal component analysis allowed the separation of the different modifiers in function of the recovery range of the analyte. The modifier W+ co-injection of Pd(NO3)2 + Mg(NO3)2 showed up as the higher positive correlation specie, because shows the higher recovery level, and so, was selected for the development of methodology for direct and simultaneous determination of Al, As, Cu, Fe, Mn and Ni in ethanol fuel by GFAAS.

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Transferência de energia entre corantes catiônicos em sistemas homogêneos/ Energy transfer between cationic dyes in homogeneous systems

Oliveira, Hueder Paulo Moisés de; Machulek Junior, Amilcar; Legendre, Alexandre de Oliveira; Gehlen, Marcelo Henrique
2003-08-01

Resumo em inglês In this work, the energy transfer by dipole-dipole interaction between cationic dyes in n-alcohols (methanol, ethanol, 1-propanol and 1-butanol) is studied by time resolved and steady state fluorescence measurements. The critical radii of energy transfer were determined by three independent methods; the spectral overlap, fluorescence decay profiles, and relative intensity measurements. In all solvents, R0 values of the dye pairs obtained from spectral overlap were between (mais) 40 to 90 Å. Steady state and time resolved fluorescence measurements resulted in values of R0 in the range of 50 - 80 Å, with good correlation of values.

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Temperature measurements by oh lif and chemiluminescence kinetic modeling for ethanol flames

Marques, Carla S. T.; Santos, Leila R. dos; Sbampato, Maria E.; Barreta, Luiz G.; Santos, Alberto M. dos
2009-01-01

Resumo em inglês OH LIF-thermometry was applied to premixed ethanol flames at atmospheric pressure in a burner for three flame conditions. Flame temperatures were simulated from energy equation with PREMIX code of CHEMKIN software package for comparison. A kinetic modeling based on a model validated through chemiluminescence measurements and on a set of reactions for nitrogen chemistry was evaluated. Marinov's mechanism was also tested. Sensitivity analysis was performed for fuel-rich fla (mais) me condition with Φ = 1.34. Simulated temperatures from both reaction mechanisms evaluated were higher than experimental values. However, the proposed kinetic modeling resulted in temperature profiles qualitatively very close to the experimental.

Scientific Electronic Library Online (Portuguese)

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Síntese e caracterização estrutural do ligante isatina-3-(N4-benziltiossemicarbazona) e do seu complexo de mercúrio(II)/ Synthesis and structural characterization of the ligand isatin-3-(N4-benzylthiosemicarbazone) and its mercury(II) complex

Fonseca, Alexandra de Souza; Peres, Gisele Louro; Storino, Tomás Garcia; Bresolin, Leandro; Carratu, Vanessa Santana; Giglio, Vinícius F.; Crespan, Estela dos Reis; Hörner, Manfredo
2010-01-01

Resumo em inglês The reaction of 4-(phenyl)thiosemicarbazide with isatin yielded a new ligand, isatin-3-(N4-benzylthiosemicarbazone). Isatin-3-(N4-benzylthiosemicarbazone) deprotonated in ethanol/KOH reacts with an ethanolic solution of Hg(NO3)2 to give a mercury complex. The compounds were characterized by IR and X-ray single crystal structure determination. The X-ray studies revealed that the complex possesses a tetrahedral geometry with two deprotonated thiosemicarbazone ligands coorde (mais) nated. The ligand and its mercury complex crystallize in the monoclinic (P2(1)/c) and triclinic (P-1) crystal system, respectively.

Scientific Electronic Library Online (Portuguese)

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Sílica quimicamente modificada com os grupos p-anisidina, p-fenitidina e p-fenilenodiamina usada como adsorvente para Pb2+, Cu2+, Cd2+ e Ni2+ em soluções aquosa e etanólica/ Silica chemically modified with p-anisidine, p-phenytidine and p-phenylenediamine groups used as adsorbent for Pb2+, Cu2+, Cd2+ and Ni2+ in aqueous and ethanol solutions

Vilar, Rossana B. C.; Jesus, Alexandre de; Benvenutti, Edilson V.; Silva, Márcia M.
2008-01-01

Resumo em inglês Silica gel was chemically modified with the aromatic amines p-anisidine, p-phenytidine and p-phenylenediamine, using grafting reactions. The resulting modified silicas were characterized by infrared spectroscopy and N2 adsorption/desorption isotherms. The organic groups were covalently immobilized in a monolayer form. These modified silicas were investigated as adsorbents for Pb2+, Cu2+, Cd2+ and Ni2+ in aqueous and ethanol solutions. In a general way, the adsorption capa (mais) city values for all adsorbents presented the following sequence: Pb2+ >> Cu2+ @Cd2+ @ Ni2+. Adsorption studies for all adsorbents, in competitive medium, showed better selectivity for Cu2+ and Pb2+ in aqueous medium and for Pb2+ in ethanol solution. Desorption studies were carried out using HCl and HNO3 as eluents.

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Simulação da Química da Atmosfera Poluída por Automóveis Movidos a Álcool/ Simulation of the urban atmosphere chemistry polluted by alcohol fueled automobiles

Pimentel, A. S.; Arbilla, G.
1997-06-01

Resumo em inglês Numerical modeling studies of urban atmospheres were performed with a photochemical box submodel which incorporates primary emission rates, temperature and solar irradiance rate coefficients. Actinic flux calculations were made for an appropriate latitude for Rio de Janeiro and initial concentrations and emission rates were taken from experimental data. The relative importance of individual reactions is discussed as well as the effect of enhanced aldehyde emissions from vehicles using ethanol and ethanol-containing fuel.

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Saponinas triterpênicas de Tocoyena brasiliensis Mart. (Rubiaceae)/ Triterpenoid saponins from Tocoyena brasiliensis Mart. (Rubiaceae)

Hamerski, Lidilhone; Carbonezi, Carlos Alberto; Cavalheiro, Alberto José; Bolzani, Vanderlan da Silva; Young, Maria Cláudia Marx
2005-08-01

Resumo em inglês The present communication reports the isolation and identification of four triterpenoid saponins from the chloroform extract of the leaves of Tocoyena brasiliensis: 3-O-beta-D-quinovopyranosyl quinovic acid, 3-O-beta-D-quinovopyranosyl cincholic acid, 3-O-beta-D-glucopyranosyl quinovic acid and the 28-O-beta-D-glucopyranosyl ester derivative of quinovic acid as binary mixtures, respectively. From the ethanol extract a flavonoid identified as ramnazin-3-O-rutinoside was ob (mais) tained. The structures of these compounds were assigned by data analysis of 1D and 2D NMR spectrometry and comparison with data recorded in the literature for these compounds.

Scientific Electronic Library Online (Portuguese)

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Relevant principal component analysis applied to the characterisation of Portuguese heather honey

Martins, Rui C.; Lopes, Victor V.; Valentão, Patrícia; Carvalho, João C. M. F.; Isabel, Paulo; Amaral, Maria T.

DRIVER (Portuguese)

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Reciclagem do crômio de resíduos químicos provenientes da determinação de carbono oxidável em fertilizantes orgânicos/ Recycling of chromium in chemical waste from oxidizable carbon determination in organic fertilizer

Machado, Jeane M. C; Oliveira, Lenita M. C. P. E; Kamogawa, Marcos Y
2011-01-01

Resumo em inglês This work proposes a separation, recovery and reuse procedure of chemical residues with chromium. This residue was generated by the determination of oxidizable carbon in organic fertilizers samples. The Cr(VI) of the residue was reduced with ethanol and precipitated with NaOH. The Cr(OH)3 precipitate was separated and oxidized to dichromate ions with hydrogen peroxide. This solution was used another time in organic carbon determination. The uses of recycled dichromate sol (mais) ution were appropriated in four successive recycling. The accuracy was proven using potassium hydrogen phthalate and ten organic fertilizer samples. The organic carbon results, determined with recycled solutions, were similar the conventional solution.

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Produção de etilenoglicóis e derivados por reações catalíticas do óxido de eteno/ Production of ethyleneglycols and derivates by catalytic reactions of ethylene oxide

Martins, Leandro; Cardoso, Dilson
2005-03-01

Resumo em inglês Products resulting from the ethoxylation of hydroxylated compounds, especially water and ethanol, are of great commercial importance. This work presents several aspects concerning the catalytic reactions of ethylene oxide, a chemical substance used in the production of a wide variety of products. Mechanisms of ethoxylation, distribution of products, formation of undesired by-products and perspectives for new processes using heterogeneous catalysis are also reviewed and discussed.

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Produção de açúcar e álcool vs. responsabilidade social corporativa: as ações desenvolvidas pelas usinas de cana-de-açúcar frente às externalidades negativas/ Sugar and ethanol production vs. corporative social responsibility: the actions taken by the sugar cane mills confronted with negative externalizations

Bragato, Ivelise Rasera; Siqueira, Elisabete Stradiotto; Graziano, Graziela Oste; Spers, Eduardo Eugênio
2008-04-01

Resumo em português A responsabilidade social corporativa (RSC) é analisada neste estudo no ambiente organizacional das usinas de cana-de-açúcar paulistas que integram o agronegócio brasileiro de açúcar e álcool. Trata-se de uma pesquisa qualitativa que utiliza dados quantitativos para fins descritivos. Apoiada em dados secundários e primários, aborda-se um estudo exploratório no contexto das usinas de cana-de-açúcar do Estado de São Paulo. O objetivo geral foi estabelecer uma a (mais) nálise comparativa entre as externalidades negativas e as ações sociais e verificar se estas últimas tinham um papel compensatório. Foi possível identificar a relação entre imagem e RSC no cenário organizacional das usinas, ressaltando as principais ações sociais desenvolvidas pelas empresas, as quais vêm contribuindo para a melhoria da imagem do setor sucroalcooleiro como agente participante do desenvolvimento sustentável. Constatou-se que o foco das ações sociais está concentrado nas áreas educacional e ambiental, ocupando um plano secundário as ações relacionadas à cultura, ao esporte e à saúde. Os resultados demonstraram que o número de projetos sociais não está necessariamente relacionado ao porte das empresas pesquisadas. Resumo em inglês Corporative Social Responsibility (CSR) is analyzed in this study in the organizational environment of sugar cane mills in the state of São Paulo and which form the Brazilian agribusiness of sugar and ethanol. Following a qualitative research, the quantitative data was used to define objectives using the primary and secondary data approach; an exploratory study in the context of the sugar-ethanol mills. The goal was to establish a comparative analysis between the negativ (mais) e external aspects and the social actions to investigate whether the latter had a significant role. It was possible to identify the relation between image and CSR in the organizational scenario of sugar-ethanol mills highlighting the main social actions developed by the enterprises which have contributed to improving the image of the sugar-ethanol sector as an active agent in the sustainable development. It was verified that the focus of social actions are concentrated in areas related to environment and education. Those related to culture, sport, and health seemed to be not as important. The results show that the number of social actions is not, necessarily, related to the size of the companies researched.

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Prevalência de tuberculose e brucelose bovina no município de Ilhéus/ Prevalence of bovine tuberculosis and brucellosis in Ilhéus, Bahia - Brazil

Ribeiro, A.R.P.; Lobato, F.C.F.; Abreu, V.L.V.; Faria, E.S.; Silva, J.A.
2003-02-01

Resumo em inglês Aiming to determining the prevalence of tuberculosis and brucellosis in Ilhéus, Bahia, Brazil, 916 cows aged 24 months or above and allocated in 85 farms were tested. The compared cervical intradermic tuberculosis and serological buffered acidified antigen (BAA), slow tube serum agglutination (STSA) and 2-mercapto ethanol (2-ME) tests were used. The prevalence of tuberculosis and brucellosis was 2.8 and 1.9%, respectively. The distribution of positive farms (10.6%) is in agreement with the notion that these diseases are widespread in the country.

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Otimização de metodologia analítica para o doseamento de flavonoides de Bauhinia cheilantha (Bongard) Steudel/ Optimization of analytic methodologies for quantifying flavonoids of Bauhinia cheilantha (Bongard) Steudel

Peixoto Sobrinho, Tadeu José da Silva; Gomes, Tiago de Lima Barros; Cardoso, Késsio Carlos de Macedo; Amorim, Elba Lúcia Cavalcanti de; Albuquerque, Ulysses Paulino de
2010-01-01

Resumo em inglês The present study examined the optimization of stabilization and extraction processes of the flavonoids of Bauhinia cheilantha (Bongard) Steudel. Four drying temperatures (room temperature, 40, 60 and 80 ºC) and seven extraction systems (distilled water, 100% methanol, 80% methanol, 100% ethanol, 80% ethanol, 80% acetone and 60% acetone) were examined. The results demonstrated a reduction in flavonoid levels with increasing drying temperatures; and 80% acetone, 80% ethan (mais) ol, and methanol p.a extraction systems were found to be most efficient and its weren't differents statisticaly (p

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Otimização das condições de produção de ésteres etílicos a partir de óleo de peixe com elevado teor de ácidos graxos ômega-3/ Optimization of the production conditions of ethyl esteres from fish oil with high content of in omega-3 long chain fatty acids

Moura, Juliana Maria Leite Nóbrega de; Gonçalves, Lireny Aparecida Guaraldo; Grimaldi, Renato; Soares, Marinalda da Silva; Ribeiro, Ana Paula Badan
2006-10-01

Resumo em inglês The production of ethyl esters by alcoholysis is an alternative for splitting triacylglycerols due to the possibility of using low temperatures, which results in oxidative protection of the polyunsaturated fatty acids. Ethyl esters produced under mild conditions of temperature could be used as substrate for obtaining structured lipids. The reaction parameters of production of ethyl esters from fish oil with high content of omega-3 fatty acids by alcoholysis were optimized (mais) using response surface methodology. An experimental design (2³) (with levels +1 and -1, six axial points with levels -alpha and +alpha and three central points) was applied. The variables investigated were concentration of catalyst, amount of ethyl alcohol and temperature. Ethyl ester conversion was monitored by high performance size exclusion chromatography (HPSEC) and the best result obtained was 95% conversion rate. The optimal conditions were 40 °C, 1% of NaOH and 36% of ethanol.

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O modelamento estatístico de misturas: experimento tutorial usando voltametria de redissolução anódica/ Statistical modeling of mixtures: a tutorial experiment using anodic stripping voltammetry

Coscione, Aline Renée; Andrade, João Carlos de; May, Gyda Marie
2005-12-01

Resumo em inglês This work illustrates the modeling procedure for a solvent mixture using the simplex- centroid approach. The selected experiment was the optimization of the peak current observed in the direct determination of nickel by anodic stripping voltammetry (ASV) in a solvent mixture composed of N,N-dimethylformamide, ethanol and water. The text is presented in a tutorial way, showing in detail the several steps which must be followed in such a process. Since not all possible mixt (mais) ures lead to a measurable instrumental response, pseudocomponents had to be used to rescale the experimental design. This also allows to show how to apply this tool, usually troublesome for non-specialists in mixture modeling procedures.

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Número de cerdas internas do órgão de Haller em larvas de Amblyomma cajennense (Fabricius, 1787) (Acari: Ixodidae) nos município de Silva Jardim e Itaguaí, RJ/ Internal setae number of the larvae Haller's organ of Amblyomma cajennense (Fabricius, 1787) (Acari: Ixodidae) from Silva Jardim and Itaguaí, RJ

Andrade, C.C.; Amorim, M.; Gazêta, G.S.; Serra-Freire, N.M.
2005-09-01

Resumo em inglês Larvae of Amblyomma cajennense (Fabricius, 1787), were obtained under laboratory conditions. The larvae were killed in hot water, preserved in 70º ethanol and prepared in definitive whole mounts. Two hundred larvae were examined under brightfield microscopy with an immersion objective in order to analyze the variation of the number of internal setae of the right and left side of the Haller's organ chamber with the purpose of utilize them as chaetotaxy parameter for specific diagnosis.

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Nova técnica para o tratamento cirúrgico da cabeça do pterígio - Exérese com álcool absoluto diluído a 50%/ New surgical technique for treatment of the pterygium head - Excision with 50% ethanol

Angelucci, Rodrigo; Simoceli, Rosângela; Oliveira, Marivaldo de Castro; Rehder, José Ricardo
2004-10-01

Resumo em português OBJETIVO: Descrever nova técnica cirúrgica para o tratamento do pterígio utilizando álcool absoluto diluído 50%. MÉTODO: A cabeça do pterígio foi submetida à exposição de gotas de álcool absoluto, diluído a 50% em água destilada, durante 40 segundos e posteriormente removida com espátula de divulsão. RESULTADOS: A excisão da cabeça do pterígio foi facilitada por plano de clivagem epitelial promovido pela aplicação do álcool diluído. O exame biomicro (mais) scópico evidenciou, após a cirurgia, superfície corneana com aspecto regular e homogêneo, o que pode contribuir para melhor qualidade de visão. CONCLUSÃO: O uso do álcool absoluto diluído a 50% com água destilada pode ser utilizado como nova técnica cirúrgica para a exérese da cabeça do pterígio da região corneana. Resumo em inglês PURPOSE: To demonstrate a new surgical technique for treatment of the pterygium head using 50% ethanol. METHODS: The pterygium head is exposed by ethanol, diluted 50% with distilled water, during 40 seconds and than removed with a surgical knife. RESULTS: Pterygium head excision was rendered easier by ethanol application. After surgery, biomicroscopy showed a regular aspect of the corneal surface allowing a better vision quality. CONCLUSION: The excision of the pterygium head by using 50% ethanol can be used as a new surgical technique for exeresis of the pterigyum head.

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Influência da variação sazonal nos teores de flavonóides e atividade antioxidante das folhas de Campomanesia adamantium (Cambess.) O. Berg, Myrtaceae/ The Influence of seasonal variation in levels of flavonoids and antioxidant activity of the leaves of Campomanesia adamantium

Coutinho, Isabel D.; Kataoka, Vanessa M. F.; Honda, Neli K.; Coelho, Roberta G.; Vieira, Maria C.; Cardoso, Claudia A. L.
2010-07-01

Resumo em português Campomanesia adamantium (Cambess.) O. Berg, Myrtaceae, é uma espécie nativa. As folhas são utilizadas na medicina popular. Os extratos hexânico e acetato de etila das folhas mostraram pouca variação na sua composição química em diferentes estações do ano associado com o desenvolvimento do vegetal, enquanto o extrato etanólico mostrou alteração significativa em relação à composição química. Todos os extratos etanólicos mostraram alta atividade antioxidante frente ao método DPPH e de moderada a alta para β-caroteno/ácido linoléico. Resumo em inglês Campomanesia adamantium (Cambess.) O. Berg, Myrtaceae, is a native species. The extracts of ethyl acetate and hexane showed little variation in their chemical composition at different seasons of the year associated with the development of the plant, while the ethanol extract showed significant change in relationship to chemical composition. All ethanol extracts showed high antioxidant activity against DPPH method and from moderate to high antioxidant activity for β-carotene/linoleic acid.

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Hidrólise Enzimática de Biomassa/ Biomass Enzymatic Hydrolysis

Ogeda, Thais Lucy; Petri, Denise F. S.
2010-01-01

Resumo em inglês Production of ethanol from biomass fermentation has gained much attention recently. Biomass cellulosic material is first converted into glucose either by chemical or by enzymatic process, and then glucose is fermented to ethanol. Considering the current scenario, where many efforts are devoted for the search of green routes to obtaining ethanol from renewable sources, this review presents the relationship between structure and properties of cellulosic material, pre-treatments and hydrolysis of cellulosic material, and structure and function of cellulase enzyme complex.

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Heterogeneidade de álcoois secundários em aguardentes brasileiras de diversas origens e processos de fabricação/ Heterogeneity of secondary alcohols in brazilian sugar cane spirits from diverse origins and processes of manufacture

Penteado, José Carlos Pires; Masini, Jorge Cesar
2009-01-01

Resumo em inglês Secondary alcohol concentrations in sugar cane spirits from different origins were determined by gas chromatography. A great variation in the concentration of the secondary alcohols was found in these spirits. Of the 33 brands analyzed, 8 of them were found to be out of conformity with the legislation. Sec butanol, for which the maximum allowed concentration level is 100 mg.L-1 in absolute ethanol, was found within a concentration range between 5 mg.L-1, the limit of quan (mais) titation (LQ) and 408 mg.L-1 in absolute ethanol. Sugar cane samples from Salinas, MG, were the only ones that exhibited self similarity because of the low concentrations of n-butanol and n-amylic alcohol (

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Gerenciamento de resíduos químicos e águas servidas no laboratório de isótopos estáveis do CENA/USP/ Chemistry waste and residues waters management at the stable isotope laboratory of the CENA/USP

Bendassolli, José Albertino; Máximo, Everaldo; Tavares, Glauco Arnold; Ignoto, Raquel de Fátima
2003-08-01

Resumo em inglês A system for disposal and recovery of the main effluents and chemical waist from isotope separation plants and enriched compounds-15N and 34S production has been carried out at the Stable Isotope Laboratory (LIE) of the CENA/USP. Around four hundred thousand liters of effluents has been recovered yearly. Among the recovered chemical wastes, the more relevant are: ammonia; brome; ammonium and sodium sulfate; sodium hydroxide; sulfur dioxide; and hydrochloric acid. Chemical (mais) wastes containg recoverable heavy metals (Ag, Cr and Cu) and solvents (methanol, ethanol and acetone) are processed and recovered. Gaseous emissions, mainly H2S are used for recovery of heavy metals solutions. The minimization of the residues waters, as well the reduction of electric energy consume was established using a water deionization system. A cost/effect balance of the process is reported.

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Fotocromismo em filmes finos de óxidos de tungstênio de diferentes composições/ Photochromism in tungsten oxide thin films of different compositions

Galvão, José R.; Scarminio, Jair
2003-08-01

Resumo em inglês Tungsten oxide thin films with three different compositions were deposited by reactive sputtering in an oxygen-argon plasma. In a system composed of a home made photochemical reactor coupled with an optic fiber spectrophotometer, the photochromic effect was studied in these oxide films as function of UV irradiation time, in ethanol, methanol and formaldehyde atmospheres. It was observed that the photochromic efficiency depends on the vapor chemical nature where the film i (mais) s irradiated as well as the film composition. Kinetic analysis suggest that two kinds of optical absorption centers should respond by the photochromic effect in these films, one generated at film surface and other inside it, which one presenting a different time constant.

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Flavonoides e outras substâncias de Lippia sidoides e suas atividades antioxidantes/ Flavonoids and other substances from Lippia sidoides and their antioxidant activities

Almeida, Macia Cleane S. de; Alves, Leonardo A.; Souza, Luciana Gregório da S.; Machado, Luciana L.; Matos, Marcos C. de; Oliveira, Maria Conceição F. de; Lemos, Telma L. G.; Braz-Filho, Raimundo
2010-01-01

Resumo em inglês The chemical investigation of the ethanol extracts of stems, roots and leaves of Lippia sidoides led to the isolation of: steroid β-sitosterol, naphthoquinone tecomaquinone, monoterpene carvacrol, flavonoid 4',5,7-trihydroxyflavanone (naringenin), 3',4',5,7-tetrahydroxyflavanone and 4',5,7-trihydroxy-6-methoxyflavone flavonoids mixture, and 3,4,4',6'-tetrahydroxydihydrochalcone-2'-O-β-D-glucopyranoside and 4,4',6'-trihydroxydihydrochalcone-2'-O- β-D-glucopy (mais) ranoside dihydrochalcones mixture. Their structures were characterized on the basis of spectral data, mainly ¹H and 13C NMR (1D and 2D) and mass spectra. The ethanol extract and isolated compounds were evaluated for their antioxidative properties using the method of inhibition of free radical DPPH (2,2-diphenyl-1-picrylhydrazyl).

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Extração de Al(III), Cr(III) e Fe(III) de meio etanólico usando o xerogel anilinapropilsílica/ Extraction of Al(III), Cr(III) and Fe(III) from ethanolic medium by anilinepropylsilica xerogel

Pavan, Flávio A.; Costa, Tania M. H.; Benvenutti, Edilson V.; Jacques, Rosângela A.; Córdova, Manuela C.
2004-10-01

Resumo em inglês In this study, the preparation of the xerogel anilinepropylsilica is reported. The ability of the xerogel for extracting Al(III), Cr(III) and Fe(III) from ethanol was investigated at 25 ºC. The xerogel adsorption capacities were obtained from the adsorption isotherms by using the batch method. Flame atomic absorption spectrometry (FAAS) was used to estimate the concentration of metal ions in solution. The adsorption affinity follows the series Cr(III) > Fe(III) > Al(III) and the maximum adsorption capacities of the metal ions were 0.61, 0.52 and 0.43 mmol g-1, respectively.

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Estudo químico e biológico de Tephrosia toxicaria Pers./ Chemical and biological study of the Tephrosia toxicaria Pers.

Vasconcelos, Jackson Nunes e; Lima, Jefferson Queiroz; Lemos, Telma Leda Gomes de; Oliveira, Maria da Conceição Ferreira de; Almeida, Maria Mozarina Beserra; Andrade-Neto, Manoel; Mafezoli, Jair; Arriaga, Angela Martha Campos; Santiago, Gilvandete Maria Pinheiro; Braz-Filho, Raimundo
2009-01-01

Resumo em inglês The ethanol extracts from leaves, stems, pods and roots were assayed against the 3rd instar Aedes aegypti larvae and the highest activity was observed in the roots extracts (LC50 47.86 ppm). This extract was submitted to partition with hexane, chloroform, ethyl acetate and methanol. The respective fractions were bioassayed and the best larvicidal activities were identified in the hexane (LC50 23.99 ppm) and chloroform (LC50 13.80 ppm) fractions. Antioxidant activity (DDPH (mais) method) was observed in the ethanol extract (IC50 276 µg/mL) from roots of T. toxicaria. Fractions from this extract were also tested and the highest antioxidant activity (IC50 89 µg/mL) was found in the methanol fraction. The flavonoids iso-obovatin (1), obovatin (2), 6a,12a-dehydro-β-toxicarol (3), 6a,12a-dehydro-α-toxicarol (4) and α-toxicarol (5) were isolated and bioassayed against A. aegypti. The flavonoid 5 showed the best larvicidal activity (LC50 24.55 ppm). The antioxidant activity of 2 was investigated and showed IC50 3.370 µg/mL. The antioxidant and larvicidal activities of Tephrosia toxicaria are reported for the first time.

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Estudo fitoquímico da madeira de Guarea macrophylla (Meliaceae)/ Phytochemical study of the wood from Guarea macrophylla (Meliaceae)

Lago, João Henrique G.; Roque, Nídia F.
2009-01-01

Resumo em inglês In the present work, the crude ethanol extract from wood of G. macrophylla was submitted to liquid/liquid partition between hexane, CH2Cl2, EtOAc and n-BuOH. Each phase was individually chromatographed over silica gel, Sephadex LH-20 or Amberlite XAD-2 to give eight terpene derivatives, such as five sesquiterpenoids (caryophyllene oxide, guai-6-en-10β-ol, spathulenol, aromadendrane-4β,10α-diol and aloaromadendrane-4α,10β-diol) as well as three tri (mais) terpenoids (cicloart-24-ene-3β,23(R*)-diol, cicloart-24-ene-3β,23(S*)-diol, and cicloart-23E-ene-3β,25-diol). Additionally, were isolated three fatty acids (linolenic, linoleic and stearic), two steroids (sitosterol and stigmasterol) and sacarose. The structures of all these compounds were characterized by spectrometric analysis, mainly mass spectrometry and NMR and comparison of these data described in the literature.

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Estudo experimental e teórico da redução de bases de Schiff derivadas da 3,3-difenilpropilamina/ Experimental and theoretical study of the reduction of Schiff bases derivated from 3,3-diphenylpropilamine

Esteves-Souza, Andressa; Echevarria, Aurea; Sant'Anna, Carlos Mauricio R.; Nascimento, Maria da Graça
2004-02-01

Resumo em inglês A series of seven Schiff bases have been synthesized from 3,3-diphenylpropilamine and substituted benzaldehydes. These imines were treated with NaBH4 in ethanol affording the corresponding amines in 98-55% yields. A molecular modeling study was performed with the Schiff bases in order to compare the theoretical parameters with the experimental results. The theoretical parameters were obtained by AM1 and PM3 semi-empirical methods. The analysis of charge, electron densitie (mais) s and LUMO coefficients suggested that the most favorable interactions should occur with Schiff bases containing electron-donating groups, in accordance with experimental yields, showing that the higher reactivity is due to higher electrophilic character of imine carbons.

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Estudo das emissões de fontes móveis na região metropolitana de Porto Alegre, Rio Grande do Sul/ Study of the emissions from moving sources in the metropolitan area of Porto Alegre - RS - Brazil

Teixeira, Elba Calesso; Feltes, Sabrina; Santana, Eduardo Rodrigo Ramos de
2008-01-01

Resumo em inglês The present study aims at assessing the influence of pollution from mobile sources on air quality in the Metropolitan Area of Porto Alegre by means of an inventory based on methods applied specifically to vehicular emissions. The study uses the method described by CETESB, based on inventories on vehicular emissions, according to USEPA methodology. Following fuel types were taken into account: gasoline (24% ethanol), alcohol, diesel oil, and CNG (compressed natural gas). R (mais) esults have shown that gasoline-powered vehicles are still responsible for emitting the highest CO and HC concentrations, while diesel-powered vehicles are the source of highest NOx, MP and SOx concentrations.

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Estudo da fermentação do hidrolisado de batata-doce utilizando diferentes linhagens de Saccharomyces cerevisiae/ Study of fermentation of the hydrolyzate sweet potato using different strains of Saccharomyces cerevisiae

Pavlak, Marta Cristina de Menezes; Abreu-Lima, Thiago Lucas de; Carreiro, Solange Cristina; Paulillo, Silene Cristina de Lima
2011-01-01

Resumo em inglês Ethanol is the most suitable substitute for oil-based fuels. The performance of the fermentation is affected by several factors, therefore the aim of this work was to evaluate the efficiency of the fermentation of a hydrolyzed must of sweet potato using three strains of the Saccharomyces cerevisiae. It was also evaluated the effect of three forms of the processes conduction in the fermentation yield, efficiency and viability of yeast at the end process. Among the paramete (mais) rs evaluated, only the cell viability showed significant difference. The strain PE-2 would be the most suitable for the fermentation of the hydrolysed sweet potato.

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Eletroanálise de derivados acetaldeído com hidrazina e determinação em amostras de álcool combustível por voltametria de onda quadrada/ Electroanalysis of acetaldehyde derivatized with hydrazine and determination in fuel ethanol by square wave voltammetry

Rodgher, Vanessa S.; Stradiotto, Nelson R.; Zanoni, Maria Valnice B.; Barros, Aquiles A.
2006-07-01

Resumo em inglês A square wave voltammetric method is described for the determination of acetaldehyde using the derivatization reaction with hydrazine sulphate, based on the reduction of hydrazone generated as a product that exhibits a single well-defined peak at -1.19V in acetate buffer at pH 5. Calibration graphs were obtained from 1.0 x 10-6 mol L-1 to 10 x 10-6 mol L-1 of acetaldehyde, using a reaction time of 8 min and a hidrazine concentration of 0.02 mol L-1. The detection limit wa (mais) s 2.38 x 10-7 mol L-1. The method was applied satisfactorily to the determination of total aldehyde in fuel ethanol samples without any pre-treatment.

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Determinação direta de molibdênio em comprimidos polivitamínicos por voltametria em meio não aquoso/ Direct determination of molybdenum in polyvitaminic tablets by voltammetry in non-aqueous media

Almeida, Alex M. de; Aleixo, Luiz M.; Andrade, João Carlos de; Coscione, Aline Renée
2006-02-01

Resumo em inglês Adsorptive stripping voltammetry carried out in a homogeneous ternary solvent composed of N,N-dimethylformamide, water and ethanol, with alpha-benzoinoxime (alphaBO) as the complexing agent for Mo(VI) and a 0.5 mol L-1 acetic acid - sodium acetate buffer as supporting electrolyte was successfully used for the determination of molybdenum in polyvitamin-polymineral tablets. Tablet samples were analyzed and the results were compared with those obtained both by graphite furna (mais) ce atomic absorption and by recovery tests, with good correlations, indicating that this may be considered as an alternative procedure for routine determination of Mo(VI) in pharmaceutical samples.

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Determinação de olanzapina em formulações farmacêuticas por espectrofotometria: desenvolvimento e validação/ Spectrophotometric olanzapine determination in pharmaceutical formulations: method development and validation

Rêgo, Jardes Figuerêdo do; Moura, Jacira Izidório de; Moita, Graziella Ciaramella
2010-01-01

Resumo em inglês Spectrophotometric methods of zero order, first and second derived order had been developed for olanzapine determination in tablets using ethanol and isopropanol as solvent. The two solvents revealed to be adequate. For the three methods the calibration curve coefficient of correlation had been greater than 0.9998 with limit of detection varying from 0.068 to 0.190 mg L-1, in ethanol, and 0.026 to 0.205 mg L-1, in isopropanol. The inter-day precision was inferior to 1.1 a (mais) nd 1.9 mg L-1 for ethanol and isopropanol, respectively. The average recoveries varied from 98 to 101%, in ethanol and 99 to 103% in isopropanol.

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Determinação de chumbo em álcool combustível por voltametria de redissolução anódica utilizando um eletrodo de pasta de carbono modificado com resina de troca iônica Amberlite IR 120/ Lead ions determination in ethanol fuel by differential pulse anodic stripping voltammetry using a carbon paste electrode modified with ion-exchange resin Amberlite IR120

Bergamini, M. F.; Vital, S. I.; Santos, A. L.; Stradiotto, N. R.
2006-01-01

Resumo em português Um método envolvendo a pré-concentração e redissolução anódica em condições de voltametria de pulso diferencial empregando um eletrodo de pasta de carbono modificado (EPCM) com uma resina de troca iônica Amberlite IR120 foi proposto para a determinação de íons chumbo em álcool combustível. O procedimento é baseado em um pico de oxidação do analito observado em -0,53 V(vs. Ag/AgCl) em solução de HCl. As melhores condições experimentais encontradas for (mais) am: 5% (m/m) da Amberlite IR120 para a construção do eletrodo, solução de HCl 0,1 mol L-1, velocidade de varredura de 10 mVs-1, tempo de pré-concentração de 15 min e amplitude de pulso de 100 mV. Utilizando essas condições, o EPCM apresentou uma resposta linear entre a corrente de pico anódica e a concentração de íons chumbo para o intervalo entre 9,9 x 10-9 e 1,2 x 10-6 mol L-1 e um limite de detecção de 7,2 x 10-9 mol L-1. Valores de recuperação entre 96 % e 102 % foram encontrados para amostras de álcool combustível enriquecidas com Pb2+ em níveis de 10-7 mol L-1. O efeito da presença de outros íons concomitantes sobre a resposta voltamétrica do eletrodo também foi avaliado. Resumo em inglês The use of pre-concentration and differential pulse anodic stripping voltammetry (DPASV) using a carbon paste electrode modified (CPEM) with ion-exchange resin (Amberlite® IR120) has been proposed for the determination of lead ions content in ethanol fuel. The lead oxidation peak was observed at -0.53 V (vs. Ag/AgCl) in HCl solution. The best DPASV response was reached for an electrode composition of 5% (m/m) Amberlite® IR120 in the paste, 0.1 mol L-1 HCl solution, scan (mais) rate of 10 mVs-1, pre-concentration time of 15 min and potential pulse amplitude of 100 mV. In these experimental conditions, the proposed methodology responds to lead ions in the concentration range of 9.9 x 10-9 to 1.2 x 10-6 mol L-1 with a detection limit of 7.2 x 10-9 mol L-1. Recoveries ranged from 96 to 102 % for Pb(II) spiked in an ethanol fuel sample at 10-7 mol L-1 level were achieved. Interferences were also evaluated.

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Determinação da entalpia de vaporização de líquidos pelo método do isoteniscópio de Smith e Menzies/ Determination of the enthalpy of vaporization of liquid compounds by the Smith Menzies (isoteniscope) method

Gerola, Adriana Passarella; Peloi, Lilian Somenci; Hioka, Noboru; Santin Filho, Ourides; Kato, Lilian Akemi
2010-01-01

Resumo em inglês This article proposes an experimental procedure to determine the enthalpy (and entropy) of vaporization of organic liquid compounds, by the Smith-Menzies (isoteniscope) method. The values of vapor pressure at different temperatures were obtained and ΔvH (and ΔvS) were graphically determined, using the Clausius-Clapeyron equation. The results for diethyl-ether, propanone, ethanol and n-hexane are in very good agreement with those from literature. A historical and (mais) thermodynamic discussion on equations that correlates vapor pressures and temperature precedes the experimental proposition.

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Desenvolvimento de método analítico para quantificação do efavirenz por espectrofotometria no UV-Vis/ UV-Vis spectrophotometry analytical method development for quantifying efavirenz

Alves, Lariza Darlene Santos; Rolim, Larissa Araújo; Fontes, Danilo Augusto Ferreira; Rolim-Neto, Pedro José; Soares, Mônica Felts de La Roca; Soares Sobrinho, José Lamartine
2010-01-01

Resumo em inglês An UV-Vis spectrophotometry analytical method for quantifying Efavirenz was developed and validated as an alternative to replace the HPLC current method. The report method presents sample concentration of 10 μg mL-1, dissolved in a solution ethanol:water (60:40, v/v), economic and technically adequate for the purpose adopted. The results and the statistical treated proved that the method being considered an precise and accurate analytical low cost alternative for lab (mais) oratory routine. The adaptability of this method in product and other analytical methods development has been challenged by mathematical calculation of drug extinction coefficient in water and methanol and practical experiments, showing interesting results.

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Descoloração redutiva de corantes azo e o efeito de mediadores redox na presença do aceptor de elétrons sulfato/ Reductive decolourisation of azo dyes and the effect of redox mediators in the presence of the electron acceptor sulfate

Costa, Mayara Carantino; Santos, André Bezerra dos; Mota, Francisco Suetônio B.; Mendonça, Glaydson Leandro Farias; Nascimento, Ronaldo Ferreira do
2010-01-01

Resumo em inglês We investigated the impact of sulphate and the redox mediator Anthraquinone-2,6-disulfonate (AQDS) on the decolorization of the azo dyes Congo Red (CR) and Reactive Black 5 (RB5). In anaerobic reactors free of extra sulphate dosage, the color removal efficiency decreased drastically when the external electron donor ethanol was removed. In presence of an extra dosage of sulphate, CR decolourisations were 47.8% (free of AQDS) and 96.5% (supplemented with AQDS). The decolour (mais) isations achieved in both reactors with RB5 were lower than the ones found with CR. Finally, the biogenic sulphide contribution on azo dye reduction was negligiable.

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Corrosão metálica associada ao uso de combustíveis minerais e biocombustíveis/ Metallic corrosion related to mineral fuels and biofuels utilization

Ambrozin, Alessandra Regina Pepe; Kuri, Sebastião Elias; Monteiro, Marcos Roberto
2009-01-01

Resumo em inglês Fuels and biofuels have a major importance in the transportation sector of any country, contributing to their economic development. The utilization of these fuels implies their closer contact to metallic materials, which comprise vehicle, storage, and transportation systems. Thus, metallic corrosion could be related to fuels and biofuels utilization. Specially, the corrosion associated to gasoline, ethanol, diesel, biodiesel, and their mixtures is discussed in this articl (mais) e. Briefly, the ethanol is the most corrosive and gasoline the least. Few investigations about the effect of biodiesel indicate that the corrosion is associated to their unsaturation degree and the corrosion of diesel is related to its acidity.

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Contribuição ao estudo alelopático de Erythrina velutina Willd: , Fabaceae/ Contribution to the allelopatic study of Erythrina velutina Willd: , Fabaceae

Centenaro, Caroline; Corrêa, Luís G. P.; Karas, Marcos J.; Virtuoso, Suzane; Dias, Josiane E G.; Miguel, Obdulio G.; Miguel, Marilis D.
2009-03-01

Resumo em português Este trabalho utilizou extrato etanólico e respectivas frações de Erythrina velutina em ensaio alelopático com sementes de Lactuca sativa. Observou-se que, com exceção da fração acetato de etila, o extrato etanólico e frações foram capazes de influenciar a germinação e crescimento das sementes de L. sativa. Resumo em inglês This work has used ethanol extract and respective fractions from Erythrina velutina in allelophatic rehearsal with seeds from Lactuca sativa. It was observed that, except for the ethyl acetate fraction, the ethanol extract and fractions has been capable to influence the germination and growth of the seeds from L. sativa.

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Constituintes químicos de Vernonia chalybaea mart./ Chemical constituents of Vernonia chalybaea mart.

Costa, Francisco José da; Bandeira, Paulo N.; Albuquerque, Maria Rose Jane R.; Pessoa, Otília Deusdênia L.; Silveira, Edilberto R.; Braz-Filho, Raimundo
2008-01-01

Resumo em inglês The chemical investigation of the hexane and ethanol extracts from aerial parts of Vernonia chalybaea conducted to the isolation and characterization of a new aliphatic tetrahydroxyl ether, along with a series of known compounds such as 4 α,10 α-epoxyaromadendrane, friedelin, taraxasteryl acetate, pseudotaraxasteryl acetate, lupeyl acetate, lupeol, α-amiryn, β-amiryn, β-sitosterol, stigmasterol, 2,3-dimethyl-1,2,3-tri-hydroxybuthanol, angophorol, (mais) angophorol-7-O-glucoside, angophorol-7-O-rutinoside, 3,7-dimethoxy-5,3',4'-trihydroxyflavone and acacetin. The structures of all compounds were determined by spectroscopic analysis and comparison with published spectral data.

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89

Constituintes químicos das raízes de Pyrostegia Venusta e considerações sobre a sua importância medicinal/ Chemical constituents from roots of Pyrostegia venusta and considerations about its medicinal importance

Ferreira, Dalva Trevisan; Alvares, Paulo Sérgio M.; Houghton, Peter J.; Braz-Filho, Raimundo
2000-02-01

Resumo em inglês This paper describes the chemical constituents isolated from roots of Pyrostegia venusta. From ethanol extract of the roots allantoin, beta-sitosterol, 3b-O-beta-D-glupyranosylsitosterol and hesperedin were isolated. The structures of these natural products were identified on the basis of spectral data, including 2D NMR of the peracetyl derivative of hesperidin.

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90

Constituintes químicos da casca do caule de Amburana cearensis A.C. Smith/ Chemical constituents of trunk bark of Amburana cearensis A.C. Amith

Canuto, Kirley Marques; Silveira, Edilberto Rocha
2006-12-01

Resumo em inglês The phytochemical analysis of the ethanol extract trunk bark of Amburana cearensis allowed the isolation and identification of twelve constituents: coumarin, sucrose, two phenol acids (vanillic acid and protocatechuic acid), five flavonoids (afrormosin, isokaempferide, kaempferol, quercetin and 4'-methoxy-fisetin), a phenol glucoside (amburoside A) and a mixture of glucosilated b-sitosterol and stigmasterol. Their structures were elucidated by spectroscopic methods such a (mais) s IR, MS, ¹H and 13C NMR, including uni and bidimensional techniques, in addition to comparison with literature data.

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91

Composição fenólica, atividade antibacteriana e antioxidante da própolis vermelha brasileira/ Phenolic composition, antibacterial and antioxidant activities of brazilian red propolis

Cabral, Ingridy Simone Ribeiro; Oldoni, Tatiane Luiza Cadorin; Prado, Adna; Bezerra, Rosângela Maria Neves; Alencar, Severino Matias de; Ikegaki, Masaharu; Rosalen, Pedro Luiz
2009-01-01

Resumo em inglês Propolis is a resinous hive product collected by honeybees from various plant sources. It has a complex chemical composition, constituted by various phenolic compounds. Extracts of increasing polarity (n-hexane, chloroform, and ethanol) were obtained from a sample of red propolis from the state of Alagoas. Assays were carried out for determination of contents of phenolics, along with antibacterial and antioxidant activities. The EEP, fractions and sub-fractions showed str (mais) ong biological activities and were related with phenolic the content compounds contents. The sub-fractions were more bioactive than the EEP and fractions, demonstrating that the antioxidant and antibacterial activities are not a result of synergistic effect between the various chemical compounds in propolis.

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92

Blainvillea rhomboidea: constituintes químicos e atividade citotóxica/ Blainvillea rhomboidea: chemical constituents and cytotoxic activity

Gomes, Regina Ferreira; Santos, Hélcio Silva dos; Albuquerque, Maria Rose Jane R.; Pessoa, Otília Deusdênia L.; Lotufo, Leticia V. Costa; Pessoa, Claudia do Ó; Moraes, Manoel Odorico de; Rodrigues, Felipe A. R.
2010-01-01

Resumo em inglês The phytochemical investigation of the ethanol extract from the aerial parts of Blainvillea rhomboidea (Asteraceae) resulted in the isolation and characterization of 8β-tigloyloxy-grazielia acid, together with the flavonoids derrone, acacetin, luteolin and luteolin 7-methyl ether, and p-(1-methyl-ethan-1-ol)-phenol. The structures of all compounds were determined by spectroscopic methods (¹H and 13C NMR and HREIMS) and comparison with published spectral data. The fl (mais) avonoids luteolin and 7-O-metyl-luteolin, isolated from the active dichloromethane fraction, showed moderate cytotoxic activity.

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93

Biodiesel de soja: taxa de conversão em ésteres etílicos, caracterização físico-química e consumo em gerador de energia/ Biodiesel from soybean: characterization and consumption in an energy generator

Ferrari, Roseli Aparecida; Oliveira, Vanessa da Silva; Scabio, Ardalla
2005-02-01

Resumo em inglês Biodiesel was produced by the transesterification of neutral soybean oil and anhydrous ethanol using NaOH as catalyst. Combinations of biodiesel and diesel in the proportions of 0, 5, 10, 20, 40, 60, 80 and 100% were tested, respectively, as fuel in an energy generator. The average consumption and mixture performance were analysed. The tests showed a reduction in Diesel oil consumption when mixed with up to 20% of biodiesel. The quality characteristics of these fuels were analyzed.

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94

Biodiesel de babaçu (Orbignya sp.) obtido por via etanólica/ Biodiesel from babassu (Orbignya sp.) synthesized via ethanolic route

Lima, José Renato de Oliveira; Silva, Rondenelly Brandão da; Silva, Carmem Cícera Maria da; Santos, Lucas Samuel Soares dos; Santos Jr., José Ribeiro dos; Moura, Edmilson Miranda; Moura, Carla Verônica Rodarte de
2007-06-01

Resumo em inglês Biodiesel was obtained by transesterification of babassu oil in anhydrous ethanol and methanol, employing NaOH as catalyst. The products obtained were characterized by physico-chemical and thermogravimetric analysis. It could be concluded that the properties of the two types of biodiesel (ethanolic and methanolic) are very similar when compared with diesel oil.

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95

Avaliação do método das adições de analito para a determinação de sódio em álcool combustível por espestrometria de emissão atômica em chama/ Evaluation of analyte additions method for sodium determination in fuel ethanol by flame atomic emission spectrometry

Oliveira, Adriana Paiva de; Okumura, Leonardo Luiz; Gomes Neto, José Anchieta; Moraes, Mercedes de
2002-01-01

Resumo em português O método empregado para a determinação de sódio por espectrometria de emissão atômica em chama, foi o das adições de analito sendo as intensidades de emissão representadas em função das concentrações de analito adicionadas às várias porções da amostra, numa faixa linear de 0 - 0,300 mg Na L-1, empregando-se 2,1 g K L-1 como supressor de ionização. Foram analisadas 20 amostras comerciais de álcool etílico hidratado combustível (AEHC), coletadas em dif (mais) erentes postos de abastecimento, na cidade de Araraquara e os resultados obtidos encontram-se no intervalo, desde menor que o limite de detecção (0,0072 mg Na L-1) até 1,55 mg Na L-1. Os limites de detecção referentes à determinação de sódio em cada amostra situam-se entre 0,0026 e 0,0239 mg Na L-1. A porcentagem de recuperação variou no intervalo de 95 a 104 %. Os desvios padrão relativos (n=12) foram £ 4,1 % para as três adições de analito, nas 20 amostras de AEHC. Resumo em inglês The analyte additions method was applied for sodium determination in fuel ethanol by atomic emission spectrometry. Graphics involving emission intensity versus analyte concentration in the 0 - 0.300 mg Na L-1 interval concentration range contaning 2.1 g K L-1 as an ionisation buffer. Twenty samples of commercial fuel ethanol were collected in differents gas stations located in Araraquara city, analyzed and results obtained varied from 0.0072 to 1.55 mg Na L-1. The limits (mais) of detecction (L.O.D.) varied from 0.0026 to 0.0239 mg Na L-1. Recoveries varied in the 95 - 104 % interval. The relative standard deviations (n=12) for three analyte additions in all samples were £ 4,1 %.

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96

Avaliação da atividade antimicrobiana do extrato etanólico bruto da casca da sucupira branca (Pterodon emarginatus Vogel) - Fabaceae/ Evaluation of antimicrobial activity of crude ethanol extract from the bark of "sucupira branca" (Pterodon emarginatus Vogel) - Fabaceae

Bustamante, K.G.L.; Lima, A.D.F.; Soares, M.L.; Fiuza, T.S.; Tresvenzol, L.M.F.; Bara, M.T.F.; Pimenta, F.C.; Paula, J.R.
2010-09-01

Resumo em português Pterodon emarginatus Vogel (Fabaceae) é uma árvore do Cerrado conhecida popularmente como "sucupira branca, faveiro, fava de sucupira e sucupira lisa" e utilizada na medicina popular em preparações anti-reumáticas, antiinflamatórias, analgésicas e antiinfecciosas. Esse trabalho teve por objetivo fazer a triagem fitoquímica do pó e avaliar a atividade antimicrobiana do extrato etanólico bruto das cascas da P. emarginatus contra bactérias Gram-positivas, Gram-neg (mais) ativas e o fungo Candida albicans. O extrato etanólico bruto foi obtido a partir das cascas dessecadas e pulverizadas. A concentração inibitória mínima (CIM) do extrato bruto foi determinada utilizando-se o inoculador de Steers. Os testes fitoquímicos detectaram a presença de flavonóides, heterosídeos saponínicos, resinas e traços de esteróides e triterpenóides. As CIM do extrato etanólico foram de 0,18 mg mL-1 para as bactérias Gram-positivas Rhodococcus equi ATCC 25923, Micrococcus luteus ATCC 9341, Micrococcus roseus IPTSP/UFG e para as bactérias Gram-negativas Serratia marcescens ATCC 14756 e Pseudomonas aeruginosa ATCC 9027; de 0,37 mg mL-1 para a Enterobacter cloacae FT 505 LEMC/EPM/UFG e de 0,74 mg mL-1 para as demais bactérias testadas e para o fungo C. albicans. O presente estudo abre perspectivas para o uso da cascas da P. emarginatus como antimicrobiano. Resumo em inglês Pterodon emarginatus Vogel (Fabaceae) is a Cerrado tree popularly known as "sucupira branca", "faveiro", "fava de sucupira" and "sucupira lisa" and has been used in folk medicine as antirheumatic, anti-inflammatory, analgesic and anti-infective. The aim of this work was to perform the phytochemical screening of the powder and to evaluate the antimicrobial activity of crude ethanol extract from P. emarginatus barks against Gram-positive bacteria, Gram-negative bacteria and (mais) the fungus Candida albicans. The crude ethanol extract was obtained from desiccated and pulverized barks. Its minimum inhibitory concentration (MIC) was determined by using Steers inoculator. The phytochemical tests detected the presence of flavonoids, saponin heterosides, resins and traces of steroids and triterpenoids. Ethanol extract MICs were 0.18 mg mL-1 for the Gram-positive bacteria Rhodococcus equi ATCC 25923, Micrococcus luteus ATCC 9341 and Micrococcus roseus IPTSP/UFG, and for the Gram-negative bacteria Serratia marcescens ATCC 14756 and Pseudomonas aeruginosa ATCC 9027; 0.37 mg mL-1 for Enterobacter cloacae FT 505 LEMC/EPM/UFG; and 0.74 mg mL-1 for the remaining tested bacteria and for the fungus C. albicans. This study opens perspectives for the use of P. emarginatus barks as an antimicrobial drug.

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97

Avaliação da atividade antibacteriana e prospecção fitoquímica de Solanum paniculatum Lam. e Operculina hamiltonii (G. Don) D. F. Austin & Staples, do semi-árido paraibano/ Evaluation of antibacterial activity and phytochemical prospection of Solanum paniculatum Lam. and Operculina hamiltonii (G. Don) D. F. Austin & Staples from the semi-arid region of Paraíba State, Brazil

Lôbo, K.M.S; Athayde, A.C.R; Silva, A.M.A; Rodrigues, F.F.G; Lôbo, I.S; Bezerra, D.A.C; Costa, J.G.M
2010-06-01

Resumo em português Devido ao aparecimento de populações de parasitos resistentes, as drogas farmacêuticas, alternativas de controle, estão sendo pesquisadas utilizando plantas medicinais. O objetivo deste estudo foi avaliar a atividade antibacteriana e realizar a análise fitoquímica do extrato etanólico de duas espécies do semi-árido paraibano, Solanum paniculatum Lam. e Operculina hamiltonii (G. Don) D. F. Austin & Staples. As referidas espécies são muito utilizadas pela popula� (mais) �ão rural contra verminoses gastrintestinais de ovinos. A prospecção fitoquímica foi obtida a partir dos extratos etanólicos para análise dos constituintes químicos existentes nas duas espécies. As análises dos extratos indicaram a presença de taninos flobabênicos, flavononóis, flavononas e alcalóides em ambas as espécies. A atividade antibacteriana foi determinada inicialmente pelo método de difusão em cavidade. A espécie S. paniculatum apresentou atividade contra Staphylococcus aureus (ATCC 12692), Escherichia coli (ATCC 25922) e Pseudomonas aeruginosa (ATCC 15442), no entanto O. hamintonii não demonstrou atividade contra as linhagens bacterianas testadas. Resumo em inglês The emergence of resistant parasite populations has led to the study of pharmaceutical drugs, which represent an alternative control. This study aimed to evaluate the antibacterial activity and to perform the phytochemical analysis of the ethanol extract from two species belonging to the semi-arid region of Paraíba State, Brazil: Solanum paniculatum Lam. and Operculina hamiltonii (G. Don) D. F. Austin & Staples. Such species have been largely used by the rural population (mais) against ovine gastrointestinal helminthes. Phytochemical prospection was obtained from ethanol extracts for analysis of chemical compounds present in both species. Extract analyses indicated the presence of condensed tannins, flavonols, flavanones, and alkaloids in both species. The antibacterial activity was initially determined by the cavity method. The species S. paniculatum had activity against Staphylococcus aureus (ATCC 12692), Escherichia coli (ATCC 25922) and Pseudomonas aeruginosa (ATCC 15442); however, O. hamintonii did not present activity against the tested bacterial strains.

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98

Análise sazonal do potencial antimicrobiano e teores de flavonoides e quinonas de extratos foliares de Aloe arborescens Mill., Xanthorrhoeaceae/ Seasonal analysis from the antimicrobial potency and flavonoid and quinone content from Aloe arborescens Mill., Xanthorrhoeaceae, leaf extracts

Cardoso, Fernando Leite; Murakami, Cynthia; Mayworm, Marco Aurélio Sivero; Marques, Lucas Miranda
2010-03-01

Resumo em português Este trabalho teve como objetivos avaliar o potencial antimicrobiano e os teores de flavonoides e quinonas de extratos foliares de Aloe arborescens Mill., Xanthorrhoeaceae, produzidos em diferentes épocas do ano. Extratos etanólicos e clorofórmicos foram preparados a partir de folhas, os bioensaios de atividade antimicrobiana foram desenvolvidos pelo método de macrodiluição em caldo, e dosagens de flavonoides e quinonas foram realizadas nos extratos. Todos os extrat (mais) os apresentaram ação inibitória sobre os microrganismos testados. O extrato clorofórmico de inverno apresentou a menor CIM (128 µg/mL) sobre B. subtilis. Os extratos clorofórmicos de inverno, primavera e verão apresentaram maior atividade antimicrobiana em relação ao extrato clorofórmico de outono. O extrato etanólico de inverno apresentou a menor CIM (256 µg/mL) e a menor CMM (512 µg/mL) sobre K. pneumoniae. Os extratos etanólicos de verão e outono mostraram baixa atividade antimicrobiana. Os teores de quinonas das folhas foram maiores nos períodos mais quentes de coleta (verão e outono), enquanto os teores de flavonoides foram semelhantes nos quatro períodos de coleta. Resumo em inglês This work has the objective of evaluate the antimicrobial potency and the content of flavonoids and quinones from the Aloe arborescens Mill., Xanthorrhoeaceae, leaf extracts produced in the four seasons of the year. Ethanol and chloroform extracts were prepared from the leaves, the bioassays from antimicrobial activity were developed by the macrodilution method in broth, and dosages of flavonoids and quinones were performed in the extracts. The winter chloroform extract s (mais) howed the lowest CIM (128 µg/mL) on B. subtilis. The ethanol extract showed the lowest CIM (256 µg/mL) and the lowest CMM (512 µg/mL) on K. pneumoniae. The summer and fall ethanol extracts showed low antimicrobial activity. The quinones extracts showed inhibitory activity on the tested microorganisms. The winter, spring and summer chloroform extracts showed higher antimicrobial activity compared to the fall chloroform one. The winter ethanol extract content from the leaves were higher in the hotter periods of collection (summer and fall) and the flavonoids content were similar in the four collection periods.

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Análise de naftoquinonas em extratos brutos de raízes de Zeyheria montana M. (bolsa-de-pastor)/ Analysis of naphtoquimones in Zeyheria montana crude extracts (bolsa-de-pastor)

Jácome, Rose Lisieux. R. Paiva; Oliveira, Alaíde Braga de; Raslan, Délio S.; Müller, Andreas; Wagner, Hildebert
1999-04-01

Resumo em inglês Four naphthoquinones, lapachol, a-lapachone, dehydro-a-lapachone and 4-hydroxy-a-lapachone were isolated from the ethanol extract of Zeyheria montana M. roots (Bignoniaceae) and were identified by spectroscopic methods. These naphthoquinones, except 4-hydroxy-a-lapachone, were quantified by HPLC, in the crude ethanol extracts of Z. montana roots. The separation of lapachol, a-lapachone and dehydro-a-lapachone was achieved and these compounds were identified in the chromat (mais) ograms by their retention times and by their on line UV-spectra. The quantification of the three naphthoquinones, in four different samples showed medium contents of 11,0 mg of lapachol, 6,1 mg of a-lapachone and 4,3 mg of dehydro-a-lapachone, in 100 mg of Z.montana roots.

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Adsorção e propriedades de volume de misturas binárias água álcool: um experimento didático com base em medidas de tensão superficial/ An undergraduate experiment in physical chemistry: adsorption and bulk properties of alcohol-water mixtures based on surface tension measurements

Santos, Michelly C. dos; Moraes, Aline P.; Lemes, Maykon A.; Lima, Emília C. D.; Oliveira, Anselmo E. de
2010-01-01

Resumo em inglês An undergraduate physical chemistry experiment based on the drop counting method for surface tension measurements is proposed to demonstrate adsorption isotherms of binary aqueous solutions of ethanol, n-propanol, and n-butanol. Excess surface is obtained by the derivative of surface tension taken with respect to alcohol activity, after this activity calculation using van Laar equation. Laboratory class contents are surface tension, excess surface, percolation of hydrogen bonds, micelle, activity, and ideal solution.

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101

A escolha da faixa espectral no uso combinado de métodos espectroscópicos e quimiométricos/ The choice of the spectral region in the use of spectroscopic and chemometric methods

Oliveira, Flavia C. C.; Souza, Antônio T. P. C. de; Dias, José A.; Dias, Silvia C. L.; Rubim, Joel C.
2004-04-01

Resumo em inglês A method is presented for the choice of spectral regions when absorption measurements are coupled to chemometric tools to perform quantitative analyses. The method is based on the spectral distribution of the relative standard deviation of concentration (s c/c). It has been applied to the development of PLS-FTNIR calibration models for the determination of density and MON of gasoline, and ethanol content and density of ethanol fuel. The new method was also compared with t (mais) he correlation (R²) method and has proved to generate PLS calibration models that present better accuracy and precision than those based on R².

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