Determination of selenium in nutritionally relevant foods by graphite furnace atomic absorption spectrometry using arsenic as internal standard

A method has been developed for the direct determination of Se in nutritionally relevant foods by graphite furnace atomic absorption spectrometry. Tungsten/rhodium carbide coating on the integrated platform of a transversely heated graphite atomizer or W coating with co-injection of Pd(NO3)(2) were used as a permanent modifiers. Samples and reference solutions were spiked with 500 mu g L-1 As and absorbance variations due to changes in experimental conditions were minimized. For 20 mu L aqueous analytical solutions delivered into the graphite tube, analytical curves in the 5.0-40 mu g L-1 with good linear correlation were established. Pyrolysis and atomization temperatures were evaluated using pyrolysis and atomization curves, respectively. The optimized heating program (temperature, ramp time, hold time) of the graphite tube of the Perkin-Elmer SIMAA 6000 atomic absorption spectrometer was: dry steps (110 degrees C, 5 s, 10 s; 130 degrees C, 15 s, 15 s); air-assisted pyrolysis step (600 degrees C, 20 s, 40 s; 20 degrees C, 1 s, 40 s); pyrolysis step (1300 degrees C, 10 s, 20 s); atomization step (2100 degrees C, 0 s, 4 s); clean step (2550 degrees C, 1 s, 5 s). The method was applied for Se determination in coconut water, coconut milk, soybean milk, cow milk, tomato juice, mango juice, grape juice and drinking water samples and four standard reference materials and results were in agreement at 95% confidence level. The lifetime of the tube was 500 firings and the relative standard deviations of measurements of typical samples containing 25 mu gL(-1) Se were 3.0% and 6.0% (n = 12) with and without internal standardization, respectively. The limits of detection were in the 0.35 mu g L-1-0.7 mu g Se L-1 range. The accuracy of the proposed method was evaluated by an addition-recovery experiment and all recovered values were in the 98-109% range. (c) 2004 Elsevier Ltd. All rights reserved.

Deputados estaduais e democracia: Valores políticos das elites parlamentares paulista e paranaense

After 20 years of reestablished democracy in Brazil, what do the state legislators think about the regime? The goal of the article is to show the views of state legislators of the Legislative Assemblies of the States of São Paulo and Paraná on democracy. For the views we use a structured and self-administered questionnaire. The results show that for the state legislators: i) democracy is stable, ii) it is superior to any other kind of regime, iii) it's support comes from some public policy and the use of voting and iv) parties and elections are important for democracy.

Alteração da expressão da Anexina-A1 e Galectina-1 na progressão do câncer colorretal esporádico

Pós-graduação em Genética - IBILCE

Associação de polimorfismos nos genes TLR2 e TLR4 com risco de câncer colorretal esporádico e influência na expressão gênica

Pós-graduação em Genética - IBILCE

Terceiro setor: interesses públicos ou privados? Um estudo de caso comparativo entre duas instituições com atuação na área social

Pós-graduação em Psicologia - FCLAS

Avaliação da remoção de compostos farmacológicos em filtro ecológico seguido por filtro de carvão granular biologicamente ativado

Pós-graduação em Engenharia Civil - FEIS

Remoção do ácido mefenâmico em solução aquosa com carvão ativado em pó e via oxidação com cloro

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Integralismo e ideologia autocrática chauvinista regressiva: crítica aos herdeiros do sigma

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeitos do resveratrol, polifenol da uva, sobre metabolismo basal e hepático, estresse oxidativo e perfil lipídico em ratos submetidos a dieta rica em sacarose e sua associação ao consumo de etanol

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Comportamento ingestivo de bovinos em sistema de pastejo rotacionado submetidos a diferentes estratégias de suplementação

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Ação mitigadora de faixa de contenção em lavouras de algodão sobre a contaminação de recursos hídricos superficiais por resíduos de pesticidas

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeito da água residuária da suinocultura no solo e na cultura do milho

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Itinerários, estruturas de sociabilidades e ação política: intelectuais de São Paulo na crise do Império (1875-1889)

Pós-graduação em História - FCHS

O sistema político, partidário e eleitoral da República de Malta

This work is a study which deals with political, electoral and party features from the Republic of Malta. An interest that motivated the study is to understand how works the consolidated two-party system in the country, the cleavages which foster that features and the Maltese media groups alignment process to those prevailing political parties. Our goal is to identify the main factors which creates and maintain those features of a two-party model in Malta, and how much it overlaps the political and electoral models applied in the country. The analysis is mostly literature, also backing up data about the nation, on elections and political parties which allow enough stability for analysis and enables us an approach about the actual facts. The survey data and literature available is mainly in English, by the lack of academic papers on Malta in Brazilian Portuguese. Therefore, this work contributes as a small panorama of the Maltese political reality, which can serve as a point of comparison and reflection on other countries' realities, with a sharp bipolar political trend, strong social entrenchment of political parties, and media groups aligned to those

Substratos orgânicos para a produção de mudas de Tabebuia heptaphylla irrigadas com água potável e residuária

Pós-graduação em Agronomia (Ciência do Solo) - FCAV