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In this work were studied the fatty acids of the fruit from Ficus benjamina, which is a tree of the Moraceae family and is largely found in Brazil as an ornamental tree, normally used for afforestation in public ways and also for indoor residences. The fruit has a diameter around 1 cm which is appreciated by several types of birds. The lipids extraction from fruit was carried out with hexane reagent, and the fatty acids were evaluated by chromatography and also by thermal analysis. The thermal characterization was done in different purge gases and heating rates. The results obtained showed that the fatty acid has a light green colour wax with a high melting point. Chromatography analysis showed that the composition of the saturated and unsaturated fatty acids was 53.48 and 46.52%, respectively. The thermoanalytical study showed that this wax has several mass losses, which are dependent on the type of purge gas used. Details regarding their kinetic behaviour were acquired and showed that the analysis at nitrogen purge gas is very similar to that observed at carbon gas. [ABSTRACT FROM AUTHOR]

For the characterization of an epoxy resin composite material, the following analyses were performed: thermal analysis (TG/DTG/DTA) in nitrogen flow at five linear heating rates and under four quasi-isothermal temperature programs, coupled TG + FTIR analysis, DSC analysis in nitrogen flow, X-ray diffraction and FTIR spectroscopy. The processing of the TG data was performed by using Netzsch Thermokinetics—a software module for kinetic analysis. The dependence of the activation energy, evaluated by isoconversional methods, on the conversion degree shows that the investigated process is a complex one. The kinetic scheme and the corresponding kinetic parameters were determined by multivariate nonlinear regression program. The kinetic scheme and kinetic parameters thus obtained were used to calculate the TG curves corresponding to the quasi-isothermal temperature programs. A good agreement between the experimental and calculated TG curves has been found. The obtained results were used for the prediction of thermal lifetime of this material corresponding to some usage temperatures and to the 5% end-point criterion. [ABSTRACT FROM AUTHOR]

Municipal sewage sludge can be chosen as an inhibitor to solve the problems related to alkali metal during biomass combustion. Emission of NO and NO is an important factor for the co-combustion of biomass with municipal sewage sludge. Thermogravimetry-mass spectrometry was adopted to study nitrogen transformation during the co-combustion of the blends. In this paper, the release characteristics of nitrogen-containing species of the blends during heating process are mainly studied. The yields of main nitrogenous gases (HCN, NH, NO and HNCO) decrease by mixing biomass with municipal sewage sludge during the heating process. The decrease rate is significant when municipal sewage sludge share changes from 0 to 30 %. The co-combustion of corn straw and cotton stalk mixed with sludge releases less nitrogenous gases than that of wheat straw mixed with sludge. [ABSTRACT FROM AUTHOR]