Abstract: The AWS A5.1 E6013 electrodes have great interest due to their wide employability. The coatings of these electrodes can alter the results of welding, making it an interesting object of study. An investigation of the chemical composition of the coatings of the electrodes AWS A5.1 E6013 from four Brazilian manufacturers was carried out using dispersive energy X-ray fluorescence spectrometry (DEXRF), scanning electron microscopy (SEM), and mass spectrometry with inductively coupled plasma (ICP-MS). Compounds such as titanium dioxide (TiO2), alkali and alkaline earth metal oxides, and carbonates were observed in the samples, in addition to Al and Si in the form of aluminosilicates. These compounds assist in the extrusion of the coating at the electrode manufacturing stage, increase the basicity of the slag and stabilize the electrical arc formed during welding. The results of the ICP-MS showed that elements such as Co, Cr, Cu, and Ni are added to increase the passivity and the mechanical resistance of the welded joint. Pb residues were observed with levels up to 700 times greater than allowed by national legislation. The presence of these metals in the coatings evidences the need for protective measures when handling the E6013 electrodes.

Resumo: Os eletrodos AWS A5.1 E6013 possuem elevado interesse devido a sua ampla empregabilidade. Os revestimentos destes eletrodos podem alterar os resultados da soldagem, tornando-se um interessante objeto de estudo. Uma investigação da composição química dos revestimentos dos eletrodos AWS A5.1 E6013 de quatro fabricantes brasileiros foi realizada usando espectrometria de fluorescência de raios-X por energia dispersiva (FRXED), microscopia eletrônica de varredura (MEV) e espectrometria de massa com plasma indutivamente acoplado (ICP-MS). Foram observados nas amostras compostos tais como o dióxido de titânio (TiO2), óxidos e carbonatos de metais alcalinos e alcalino-terrosos, além de Al e Si na forma de aluminosilicatos. Estes compostos auxiliam na extrusão do revestimento na etapa de fabricação do eletrodo, elevam a basicidade da escória e estabilizam o arco elétrico formado durante a soldagem. Os resultados do ICP-MS mostraram que elementos como Co, Cr, Cu e Ni são adicionados para aumentar a passividade e a resistência mecânica da junta soldada. Resíduos de Pb foram observados com teores até 700 vezes maior que o permitido pela legislação nacional. As presenças destes metais nos revestimentos evidenciam a necessidade de medidas protetivas ao manipular os eletrodos E6013.

RESUMO Objetivo Neste trabalho, foram estudados diferentes tipos de suplementos esportivos contendo proteína de soro de leite, conhecidos como: whey protein, hipercalóricos e barras de proteína. Métodos Um procedimento de preparo de amostras foi estudado com o emprego de digestão úmida assistida por micro-ondas, a fim de determinar os teores de cromo e manganês por espectrometria de absorção atômica em forno de grafite. Resultados Os métodos adotados apresentaram boa exatidão (recuperações na faixa de 90 a 109%) e precisão (Desvio padrão relativo <8%). Embora tenha sido obtida uma capacidade de detecção adequada de 50ng g-1 para o manganês e de 65ng g-1 para o cromo, o método de preparo da amostra também se revelou adequado para a utilização em análises por espectrometria de massas com plasma indutivamente acoplado. O método foi aplicado a 26 amostras comerciais, cujas concentrações de cromo variaram entre 0,22 e 1,0μg g-1, e de manganês entre 2,0 e 37μg g-1. Conclusão Os resultados obtidos por absorção atômica, para ambos os analitos, mostraram-se de acordo com aqueles obtidos por espectrometria de massas. Além disso, algumas amostras apresentaram concentrações de cromo acima da recomendação de consumo diário e, como resultado, a técnica de difração de raios-X em pó foi utilizada como ferramenta analítica para avaliar o estado de oxidação do cromo em tais amostras.

ABSTRACT Objective In this paper, we studied three different types of ordinary sports supplements containing whey protein: whey protein-based ones, hypercaloric ones, and protein bars. Methods A sample preparation procedure was studied employing microwave-assisted wet digestion in order to determine the Chromium and Manganese levels by graphite furnace atomic absorption spectrometry. Results The developed methods have presented good accuracy (recoveries in the range of 90% to 109%) and precision (Relative standard deviation <8%). Although an adequate detectability was obtained (50ng g-1 for Manganese and 65ng g-1 for Chromium), the sample preparation method was also adequate to inductively coupled plasma mass spectrometry analysis. The method was applied to 26 commercial samples, in which the Chromium concentrations were in the range between 0.22 and 1.0μg g-1 and the Manganese concentrations varied from 2.0 to 37μg g-1. Conclusion The results obtained by atomic absorption for both analytes were in agreement with those obtained by mass spectrometry. In addition, some samples presented concentrations of Chromium above the recommended daily intake and, as a result, we used the X-ray powder diffraction technique as an analytical tool to evaluate the oxidation state of Chromium in such samples.

Resumo Este trabalho descreve a análise de tecidos comestíveis de frango como coração, fígado e moela, crus e cozidos com temperos em diferentes panelas (panela de ferro, panela de alumínio e panela de alumínio batido) comumente utilizadas no Brasil. A digestão ácida assistida por radiação micro-ondas, com utilização de ácido nítrico diluído, foi empregada para decomposição das amostras. Os teores dos elementos metálicos Al, Ca, Cu, Fe, Mn e Ni foram determinados por Espectrometria de Emissão Óptica com Plasma Induzido por Micro-ondas. A comparação dos teores de Fe obtidos também por Espectrometria de Absorção Atômica em Chama mostrou uma boa exatidão do método. Os limites de quantificação para os analitos avaliados ficaram abaixo de 0,011 mg kg-1, mostrando detectabilidade adequada. As cocções das amostras nas diferentes panelas utilizadas promoveram um aumento dos teores de cinzas e proteínas e uma diminuição dos teores de umidade. A Análise de Componentes Principais e os diagramas de caixa mostraram que as variáveis Ca e Fe apresentaram as maiores variações entre as amostras, seguidas pelas variáveis Al e umidade. As variáveis Al, Cu, Mn, Ni, cinzas e proteínas apresentaram comportamento semelhante após a cocção nos três tipos de panela empregados. A amostra de fígado cozida tanto na panela de ferro quanto na panela de alumínio batido apresentou teores similares de Fe, enquanto as amostras de coração e moela apresentaram teores similares de Ca após cocção nas mesmas panelas.

Abstract This work describes the analysis of different chicken tissues (gizzard, heart, and liver) both raw and cooked with seasonings in different types of cooking pots (iron pot, , aluminum pot and hammered aluminum pot) commonly used in Brazil. The samples were decomposed using microwave-assisted digestion with diluted nitric acid; and the contents of Al, Ca, Cu, Fe, Mn and Ni were determined using Microwave Induced Plasma Optical Emission Spectrometry (MIP OES). The Fe content was also determined by Flame Atomic Absorption Spectrometry, and the comparison showed good accuracy of the method. The limits of quantification were below 0.011 mg kg-1, showing adequate detectability. Cooking in the different pots increased the ash and protein contents as well as decreased the moisture content. Box-plot and Principal Components Analysis showed that Ca and Fe contents present the largest variations in the samples, followed by Al and moisture. The variables Al, Cu, Mn, Ni, ash, and protein presented similar behavior after cooking in all different pots. In addition, liver cooked in both iron and hammered aluminum pots presented similar Fe contents, while gizzard and heart showed similar Ca contents.

Abstract Nutritionally, cheese and other dairy products have been highlighted especially as a calcium source. Access to minerals is dependent on variables related to diet, lifestyle, and also the health status. This study aimed to evaluate the bioaccessibility and calcium partition in Minas Padrão cheese over its ripening period for experimentally obtained samples. The cheese of the study has been manufactured using two different technologies (A and B). Also to evaluate the evolution of pH over cheese ripening and the influence of calcium partitions in its bioaccessibility along the cheese ripening period. The mean values found for total calcium content were (549 mg⋅100 g-1 – A and 644 mg⋅100 g-1 – B). For calcium in the aqueous phase on average 460 mg⋅100 g-1 – A and 404 mg⋅100 g-1 – B. These and other changes found are possibly due to physicochemical and biochemical changes, especially with respect to pH variations. Calcium bioaccessibility decreased in the beginning and then incresed in the end of the ripening period. The results obtained in this work hopefully may allow further studies and the development of products in which calcium bioaccessibility might be indicated on the product`s label accordingly to its ripening time.

Abstract A 32 factorial design was employed to develop an in vitro digestion method for estimation of Fe bioaccessible fractions in cooked chicken meat. The effects of sample size and the in vitro bioaccessible fractions of this essential element were evaluated. A sample preparation method employing a microwave assisted digestion with dilute nitric acid was used prior to total Fe determination. For the bioacessibility studies, the optimized procedure employed 7.5 g of sample and 6% w/v of an acid pepsin solution. This procedure was applied to two kinds of chicken meat samples: breast and liver. Flame Atomic Absorption Spectrometry was used to determine total and bioaccessible (chyme or soluble portion) levels of iron in the samples. With respect to total Fe content, the bioaccessible fractions of Fe found in these samples were around 23% and 56 %, for breast and chicken liver, respectively. The chicken liver sample showed the highest total (400 ± 10 mg kg-1) and bioaccessible Fe contents (223 ± 18 mg kg-1) and stands out as a good source of this micronutrient.

Increased production of biomass is currently the only immediately accessible alternative for large-scale carbon sequestration and it can produce large amounts of food, fuel and raw materials for the chemical industry that can in turn growingly replace oil as a source of organic building blocks and also of hydrogen and sulfur. Development of processes for biomass and abundant minerals transformation into chemical raw materials should now benefit from large inputs from nanotechnologies, biotechnologies, information and micro-reactor technologies. Success in R&D&Innovation along this line can yield new products and processes needed to perform desirable functions within a sustainable development paradigm.

A determinação de espécies inorgânicas em adoçantes líquidos à base de ciclamato-sacarina e esteviosídeo é descrita. O método, sem tratamento prévio da amostra, é baseado na espectrometria de emissão óptica em plasma com acoplamento indutivo. Parâmetros instrumentais foram otimizados de acordo com a robustez do plasma e a razão sinal analítico/ sinal de fundo. A exatidão foi avaliada para As, Ca, Cd, Co, Cu, Fe, Mg, Mn, Ni, Pb e Zn empregando experimentos de adição e recuperação. Os valores de recuperação ficaram entre 90 e 110% para a maioria dos analitos, os RSDs obtidos foram, em geral, menores que 5% e os limites de detecção ficaram na faixa de 0,7 (Mg) a 71 (Pb) µg L-1. Não foi detectada a presença de As, Co e Pb. As concentrações de Cu e Zn foram semelhantes para as amostras de ciclamato-sacarina e esteviosídeo enquanto as demais espécies mostraram diferenças.

An analytical method for the determination of inorganic species in liquid cyclamate-saccharin and stevioside sweeteners is presented. The method is based on inductively coupled plasma optical emission spectrometry and allowed analysis without prior sample treatment. Instrumental parameters were optimized according to plasma robustness and the signal to background ratio. The accuracy of the method was evaluated for As, Ca, Cd, Co, Cu, Fe, Mg, Mn, Ni, Pb, and Zn employing analyte addition and recovery experiments. The recovery values were between 90 and 110% for the majority of the analytes, the RSDs obtained were, in general, lower than 5% and the limits of detection were in the range 0.7 (Mg) - 71 (Pb) µg L-1. The analyses of different samples indicated that the average values of many of the analytes studied were different for the two types of samples. Copper and Zn concentrations were in the same range and As, Co, and Pb were not detected in any samples.

Inductively Coupled Plasma Optical Emission Spectrometry was used to determine Ca, Mg, Mn, Fe, Zn and Cu in samples of processed and natural coconut water. The sample preparation consisted in a filtration step followed by a dilution. The analysis was made employing optimized instrumental parameters and the results were evaluated using methods of Pattern Recognition. The data showed common concentration values for the analytes present in processed and natural samples. Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA) indicated that the samples of different kinds were statistically different when the concentrations of all the analytes were considered simultaneously.

Polyaniline (PAni) is one of the most studied conducting polymer. It can be synthesized by two methods: electrochemical or chemical oxidation. The chemical oxidation is more adequate to produce large quantities of polymer. Regardless of the synthesis scale, the treatment of the residues before its final destination is very important and necessary because it contains toxic aniline derivatives (carcinogens in some cases), acids and inorganic salts, both with low toxicity. In this work we discuss the methods used to treat these residues and to eliminate and discard the toxic substances. These were extracted from the reaction residues by using activated coal and the pH of the residue was neutralized.