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This paper aims the treatment of leachate in a reactor in batches using the advanced oxidation process via Fenton, allowing partially oxidize organic compounds and making them biodegradable, being removed by filtration or sub-2 Diovana Aparecida dos Santos Napoleão et al.sequent biological treatment. This technique allows to verify the satisfactory operating conditions for greater removal efficiency of both organic load as nutrients. The process was modeled via neural network of the kind feedforward and backpropagation. The best configuration to represent the relationship between the variation in chemical oxygen demand (network output layer) and the factors presence or absence of lime, time, pH, volume of hydrogen peroxide solution and concentration of Fe 2+ (network input layer) was obtained with 12 neurons in the hidden layer and the tangent sigmoidal transfer functions. The correlation coefficients above 0.99 for the phases of training and simulation show the power of the generalization of neural model obtained.

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Inventado no Século XIX, os carros elétricos não foram competitivos o suficiente para disputarem mercado com os carros a combustão durante o Século XX. Com o crescimento do pensamento sustentável e do debate sobre poluição, meio ambiente e mudança climática, a queima de combustíveis fósseis e a poluição gerada pelo processo se tornaram pontos críticos no debate ecológico. Devido à urgência da mudança climática, maiores investimentos foram realizados em tecnologias que minimizem o problema e empresas com propostas mais ecológicas surgiram no mercado. Este trabalho teve como objetivo concatenar e comparar as principais conclusões disponíveis na literatura contemporânea a respeito do uso de carros elétricos a bateria, a fim de descrever seus impactos ambientais, principalmente quando comparados aos carros convencionais. Concluiu-se que a mudança para carros elétricos é ambientalmente positiva quando conciliada à mudança de matriz energética para fontes renováveis, chegando a uma redução de 34% nas emissões de gases de efeito estufa, em determinados estudos. Porém, ressalta-se que houve grande variabilidade de resultados quanto às reduções de emissões desses gases, com estudos similares alcançando resultados que diferiam 4,5 vezes entre si, devido às premissas utilizadas. Encontraram-se também alternativas para potencializar esta migração de tecnologia de transporte, como políticas de taxação de carbono. Pontuaram-se aspectos negativos dos carros elétricos, como acidificação oceânica e do solo e alta toxicidade humana comparada aos carros a combustão.

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One of the problems that concerns engineering courses in Brazil is the students low level of motivation in regarding the type of teaching and, as a consequence, low academic performance. This article encourages the introduction of active methods in Engineering teaching, emphasizing the methodologies of Project Based Learning. The approach used was proposing a project for students to analyze important aspects in the production of cylindrical cans. The students applied calculus concepts and developed a model for the optimal dimensions of the cylinder and the utilization of the plates used. Characteristics of two materials used in the manufacture of these cans (tinplate and aluminum) were also gotten. Such aspects are relevant for both environmental sustainability and production costs. Concepts of application of derivatives and Fermat's theorem were used, learned in the discipline of Differential and Integral Calculus, in order to obtain the maximum and minimum values of an established function which relates the dimensions of the can and the amount of material needed. The dimensions obtained theoretically proved to be close to the real values found in cans available on the market. After analyzing the resistance to corrosion, the cost, the decomposition time and the mechanical resistance, it was concluded that the most appropriate material for the production of cans was the tinplate. In this context, teaching with Project Based Learning methodologies may contribute to innovative teaching practices in the training of engineering professionals, overcoming the limitations of traditional teaching methods.