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Leite N.F.,Institute Tecnologia do Parana TECPAR | Peralta-Zamora P.,Federal University of Parana | Grassi M.T.,Federal University of Parana
Journal of Environmental Sciences | Year: 2011

The concentrations of 16 polycyclic aromatic hydrocarbons (PAHs) were determined in surface sediment samples from nine sites located at the Iguaçu River Basin in the Metropolitan Region of Curitiba, Brazil to evaluate their distribution and sources. The total concentration of the PAHs was greater for sediments from highly urbanized areas, while the sediments from the Iraí Environmental Protection Area (Iraí EPA) showed significantly low concentrations. The sediments from the Iguaçu and Barigui rivers were classified as highly contaminated, while those from the Cercado and Curralinho rivers were classified as moderately contaminated. The predominance of PAHs containing two to four aromatic rings in most of the samples suggested the direct input of raw sewage into the water resources evaluated. Benzo[g,h,i]perylene, dibenzo[a,h]anthracene and indeno[1,2,3-cd]pyrene were predominant in sediments from the areas under the greatest urban and industrial development. The correlation between thermodynamic stability and the kinetics of evolution presented by the isomeric pairs indicated that combustion is the predominant source of PAHs in the sediments because the combustion of fossil fuels affected most of the points evaluated, followed by combustion of biomass and eventually combustion of oil product inputs. In general, the results showed that areas under strong urban influence, as well as the Iraí EPA, receive contributions of PAHs from similar sources. © 2011 The Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences. Source

Chaves E.S.,Federal University of Santa Catarina | dos Santos E.J.,Institute Tecnologia do Parana TECPAR | Araujo R.G.O.,Federal University of Sergipe | Oliveira J.V.,URI Integrated Regional University Brazil | And 2 more authors.
Microchemical Journal | Year: 2010

Methods for the determination of 5 major (Ca, K, Mg, Na and P) and 14 minor elements (Al, Ba, Cd, Co, Cu, Fe, Ga, Mn, Mo, Ni, Pb, Rb, Sr and Zn) in vegetable seeds by ICP OES and by ICP-MS, respectively, are proposed. After a common sample preparation consisting of smashing and homogenization in an agata mortar, followed by acid digestion in a microwave oven, the diluted sample solutions were measured in the spectrometers using conventional pneumatic nebulizers. External calibration with aqueous standard solutions was used for both techniques. Internal standard was not required, due to the absence of non-spectral interference. For the major elements, the detection limits were in the range of 0.01 (Mg) to 0.3μgg-1 (Na and K) and for the minor elements they were in the range of 0.001 (several) to 0.4μgg-1 (Fe). The detection limits were adequate for the seed analysis. The accuracy was validated by analyzing a botanical certified reference material (Pine Needles). Agreement of the concentrations with the certified or informed values was obtained, according to the t-test for a confidence level of 95%. The relative standard deviations were below 10% indicating an adequate precision. Seeds from seven different plants were analyzed: cotton seed, sunflower, castor bean, fodder turnip, curcas bean, soybean and tung. The element concentrations varied considerably in the different samples. The results were also evaluated using the principal component analysis. © 2010 Elsevier B.V. Source

Da Silva E.J.,Federal Technological University of Parana | Torquato E.,Pontifical Catholic University of Parana | Ramos M.P.,Institute Tecnologia do Parana TECPAR | Paraiso E.C.,Pontifical Catholic University of Parana
Proceedings - 2013 IEEE International Conference on Systems, Man, and Cybernetics, SMC 2013 | Year: 2013

Collaboration is an important issue when developing software, because it involves working together towards a common goal. This work presents OPERAM, a collaborative semantic workspace that allows comparing the modeling performed at earlier stages of software development with JAVA code. OPERAM provides useful information for professionals involved in the task of developing code and even managing the project. OPERAM aims to allow monitoring of the project, helping users to be aware of the context they are working, allowing carry out verification of software development, confronting the modeling performed with source-code produced during the programming phase. We present its main features and architecture. In this paper the main features and architecture of OPERAM are presented, as well as a validation was conducted to prove the effectiveness of OPERAM. The results show the value of the workspace as a tool to support collaboration and software verification. © 2013 IEEE. Source

Barison A.,Federal University of Parana | Da Silva C.W.P.,Federal University of Parana | Campos F.R.,Federal University of Parana | Simonelli F.,Federal University of Parana | And 2 more authors.
Magnetic Resonance in Chemistry | Year: 2010

A simple methodology for the determination of the fatty acid composition of edible oils through 1H NMR is proposed. The method is based on the fact that all fatty acid chains are esterified to a common moiety, glycerol, and the quantification is done directly in the 1H NMR spectra through the relationship between the areas of a characteristic signal of each fatty acid and a signal of the glycerol moiety, without the use of mathematical equations. The methodology was successfully applied to determine the fatty acid composition of several edible oils, with equivalent results to those given by the AOAC Official method by gas chromatography. Itsmain advantages are simplicity and the lack of need for sample pre-treatment such as derivatization or extraction. Copyright © 2010 John Wiley & Sons, Ltd. Source

Packer A.P.,EMBRAPA - Empresa Brasileira de Pesquisa Agropecuaria | Sarkis J.E.S.,Brazilian Nuclear Energy Research Institute (IPEN) | Dos Santos E.J.,Institute Tecnologia do Parana TECPAR
Journal of the Brazilian Chemical Society | Year: 2014

The presence of some inorganic elements in biodiesel can compromise the fuel quality and enhance the emission of pollutants. In this context, a new procedure for biodiesel sample preparation using a high pressure asher (HPA) is presented, aiming the determination of Al, Ca, Cu, Fe, K, Mg, Mn, Na, Ni, P, Sr, and Zn, in soybean, sunflower, animal fat, cotton and castor oil, by inductively coupled plasma optical emission spectrometry (ICP OES). The digestion conditions of the HPA were optimize to digest 1.5 g of biodiesel, with HNO3 and H2O2, at a temperature of 300 °C and pressure of 435 psi, which considered the sample dilution factor, the total solids in solution and the acidity for ICP OES determinations. Analytes concentrations in these biodiesels were calculated using standard addition method. Detection limits from 0.05 to 0.7 mg kg-1 were suitable to attend biodiesel quality parameters, government policy and legislations worldwide. Therefore, the proposed procedure proved to be efficient to eliminate the major organic interferences typically present in oil based samples allowing a fast, precise, interference-free and robust analytical condition for biodiesel characterization. © 2014 Sociedade Brasileira de Química. Source

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