Biodiesel fuels are attracting increasing attention worldwide as an environmentally friendly fuel. Despite the numerous advantages of biodiesel compared with diesel, some studies indicate that biodiesel is more susceptible to oxidation and therefore more corrosive to metals. The research indicates that stainless steel, cast iron, galvanized steel, carbon steel, and aluminum materials are relatively compatible with pure biodiesel, whereas copper, bronze, brass, lead, tin, zinc, and iron are incompatible, decreasing the stability of biodiesel and increasing its corrosiveness. The use of synthetic antioxidant additives for biodiesel is a necessity to minimize its susceptibility to oxidation. The efficiency of a given antioxidant depends on the feedstock used for biodiesel production. In general, the effectiveness of order of antioxidants was pyrogallol>propyl gallate>Ethanox4760E>N,N′-di-sec-butyl-p-phenylenediamine>2,2′-methylene-bis-(4-methyl-6-ter-butylphenol)>2-tert-butyl-4-hydroxyanisole and 3-tert-butyl-4-hydroxyanisole>2-(1,1-dimethylethyl)-1,4-benzenediol [tert-butylhydroquinone (TBHQ)]∼2,6-bis(1,1-dimethylethyl)-4-methylphenol>2,5-di-tert-butyl-hydroquinone>α-tocopherol. There are few studies showing the effect of inhibitors on the corrosion of metals in biodiesel. Antioxidant compounds may also act as a corrosion inhibitor, but the mechanism of action of these corrosion inhibitors is the formation of a persistent adsorbed monolayer film at the metal/solution interface. For example, the antioxidant TBHQ used in biodiesel retarded the corrosion process in copper, carbon steel, and galvanized steel, acting as a corrosion inhibitor through the formation of a protective film layer.

Various host compounds have been investigated to produce an alternative attractant for monitoring and controlling pest insects. Several studies evidenced that volatile molecules released by coffee and mangoes attracted both male and female Ceratitis capitata (Wiedemann), a significant pest in fruit crops. In this study, we tested the effectiveness of the commercial glycolic extract of coffee (Coffea arabica L.) and a commercial mango essence (Mangifera indica L.) to attract C. capitata. We identified the main volatile compounds (VOCs) emitted from such products. The experiments were conducted in field cages and showed that the glycolic extract of coffee attracts both sexes of C. capitata, while the mango essence attracts only males. After seven days, the pH of the coffee extract and mango essence did not change. These results indicate that attractants based on commercial fruit extracts and essences can be an option for integrated pest management of the Mediterranean fruit fly in orchards.

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Anastrepha dissimilis is currently considered to be widely distributed in Brazil, occurring in 20 of 27 states. However, morphological differences between the holotype (from Plaisance, Haiti) and a paratype (from Pernambuco, Brazil) suggest that the Brazilian specimens are not A. dissimilis, because their aculeus tip is similar to the paratype not to the holotype. Therefore, considering the importance of integrative taxonomy for species delimitation, we used geometric and linear morphometrics and cytochrome c oxidase subunit I sequences integrated with the morphology of the aculeus tip to clarify the identity of populations previously identified as A. dissimilis from multiple Brazilian localities. Morphological data show a uniform pattern among the Brazilian populations, with some variation among specimens from the south and northeast. In addition, the geometric and linear morphometrics suggest considerable geographic variation among these populations, suggesting the existence of at least two morphs. The molecular analysis revealed that specimens from Brazil previously identified as A. dissimilis belong to Anastrepha chiclayae Greene, with a genetic distance ranging from 0.00 to 0.015%. According to our integrative analyses, specimens from Brazil formerly identified as A. dissimilis actually are A. chiclayae. Therefore, this is the first record of A. chiclayae in Brazil, and we also report that A. dissimilis does not occur in Brazil.

RESUMOO biodiesel está atualmente em uso como um combustível alternativo adicionado ao diesel. A meta do governo brasileiro é aumentar gradativamente a concentração do biodiesel à medida que crescer a produção deste biocombustível no país. Considerando que o biodiesel é mais corrosivo que o diesel, este aumento em sua concentração tornará o problema da corrosão metálica cada vez maior, podendo levar a grandes prejuízos econômicos. Este trabalho apresenta um mapeamento de patentes e artigos relacionados às tecnologias para inibir a corrosão causada aos metais por combustíveis. A metodologia de busca de artigos na base de dados Scopus utilizou as palavras-chave fuel*, corrosion* inhibitor*. Para a busca de patentes na base de dados Espacenet utilizou o cruzamento de dois códigos, C23F11 que se refere ao uso de inibidores de corrosão metálica e C10L1 que diz respeito a combustíveis líquidos carbonáceos quando foram encontradas inicialmente 856 patentes.

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Este projeto avaliou o desempenho de um sistema para tratamento de esgoto sanitário operando de modo contínuo e sem recirculação da fase líquida. O trabalho se diferencia por utilizar a bucha vegetal de curcubitácea como material suporte do reator, pouco estudada para essa finalidade de tratamento biológico de efluentes. Esse material se caracteriza por ser leve, barato e facilmente encontrado na região do alto sertão alagoano, além de ser integralmente natural e com características favoráveis à imobilização de biomassa. A bucha curcubitácea vem se mostrando bastante eficiente para o tratamento de efluentes líquidos, relacionando os conceitos de sustentabilidade e eficiência. Foi utilizado um reator anaeróbio, em escala de bancada, de leito fixo e fluxo contínuo de escoamento ascendente. O desempenho do sistema foi avaliado em três diferentes tempos de detenção hidráulica (TDH), 8, 6 e 4 horas. Os valores efluentes médios para nitrogênio amoniacal foram de 22,71 mg N/L; 27,97 mg N/L; e 32,40 mg N/L para tempos de detenção hidráulica (TDH), 8, 6 e 4 horas, respectivamente. Em termos de remoção de matéria orgânica representada pela DQO, o reator apresentou eficiência média de 73,0%, 59,7% e 64,0% para cada tempo estudado. Nesta pesquisa, foi desenvolvido um sistema de tratamento de esgoto sanitário estável, confiável e eficiente, em escala de bancada (experimental), baseado nos princípios do tratamento de efluentes por via biológica. Palavras-chave: Esgoto sanitário, biomassa imobilizada, amonificação.