ARTICLE This journal isIn this work, we have synthesized ozonides from sunflower, flaxseed and baru oils. In addition, ozonolysis reaction of sunflower oil in the presence of water was performed, and the product obtained had high viscosity and a gel-like appearance. The ozonated products were investigated for their antimicrobial activity and cytotoxicity . The oleogel, with an MIC ≤ 3 mg mL -1 , exhibited excellent antimicrobial activity against standard and clinical strains. All products showed no cytotoxicity when tested against NIH/3T3 murine fibroblast cells . Effects of ozonation time on the oils were analyzed by IR, 1 H and 13 C NMR spectroscopy. DSC analysis shows that the ozonides of vegetable oils decompose with a peak at about 150 o C and with a broad exotherm. The decomposition enthalpy is proportional to the degree of ozonation reached.

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Neste trabalho sistemas agroflorestais (SAFs) são caracterizados e discutidos sob a ótica da produção ruralsustentável. Propõem-se modelos de associações entre agricultura, pecuária e espécies florestais, adaptando estaspráticas à realidade regional. A implantação desses sistemas agroflorestais visa também proporcionar um padrãorazoável de qualidade de vida com a utilização da mão-de-obra familiar, bem como a auto-gestão das atividadesagrossilvipastoris por parte das comunidades rurais envolvidas, privilegiando-se desse modo associações ecológicassustentáveis próximas dos ecossistemas naturais. As alternativas expostas podem também conduzir a uma inserçãode pequenos produtores rurais no mercado de trabalho, hoje marginalizados em função do sistema agropecuáriovigente.

Titanium dioxide has attracted much attention since a long time ago due to its versatility as advanced material. However, its performance as semiconductor devices is very much dependent on the predominant crystalline phase and defect concentrations, which can be adjusted through the synthesis methods, thermal treatments and doping processes. In this work, an accurate structural characterization of titanium dioxide was used by X-ray diffractometry supported by rietveld refinement and thermal analysis. The insertion of 5 mol% of zirconium silicate was able to stabilize anatase up to 900 C, permitting the oxygen vacancies to be significantly eliminated. It was demonstrated also that the changes in the isotropic thermal parameters for oxygen are related to reconstructive transformation necessary to promote the anatase-to-rutile phase transition. Independently of doping process, the crystallization process of anatase phase as a function of temperature increasing occurs exclusively due the reduction of lattice microstrain up to 600 C. However, above 650 C, that crystallization process becomes dependent of the increasing in crystallite size. The anatase crystallite growth event was only possible when the titanium dioxide was doped with zirconium silicate. Otherwise, the rutile phase amount starts to rise continually. Thus, there are optimistic expectations for that new composition to be a new semiconductor matrix for additional doping processes.

Urea is a compound widely used as a feed additive for ruminants; however, when used profusely, it can lead animals to intoxication. Another factor that affects the effectiveness of urea is the lack of synchronization between the nitrogen and the availability of carbohydrates, necessary for better development of the ruminal microbiota. In order to circumvent these problems and improve the efficiency in urea use, the present study developed two new nutritional additives (F16 and F17) with different carbohydrate sources. One of the products developed (F16) used sugarcane molasses as a carbohydrate source, while the other (F17) used cassava starch. In addition to the carbohydrate source, both products contained the same amounts of urea, sulfur, calcium carbonate and were coated with carnauba wax. The supplements developed and two other commercial products based on extruded urea (UE) and polymer-coated urea (UP) were tested for solubility and cumulative gas production. The wax used in the coating process of the developed products (F16 and F17) proved to be efficient in reducing the solubility of the ingredients used. During chemical composition analysis it was verified that both supplements developed contained protein equivalent above 150% of crude protein. The cumulative gas production showed a higher production related to the product F17 (p < 0.05). Through thermogravimetric analysis, it was found the chemical integrity of the ingredients that make up the supplements developed. Therefore, is possible to reduce the solubility of urea using carnauba wax as a coating material. The formula with cassava starch associated with urea (F17) had a better synchronization during the degradation of its ingredients.