In the framework of Monitoring by Ocean Drifters (MONDO) project, a set of Lagrangian drifters were released in proximity of the Brazil Current, the western branch of the subtropical gyre in the South Atlantic Ocean. The experimental strategy of deploying part of the buoys in clusters offers the opportunity to examine relative dispersion on a wide range of scales. Adopting a dynamical systems approach, the authors focus their attention on scale-dependent indicators, like the finite-scale Lyapunov exponent (FSLE) and the finite-scale (mean square) relative velocity (FSRV) between two drifters as a function of their separation and compare them with classic time-dependent statistical quantities like the mean-square relative displacement between two drifters and the effective diffusivity as functions of the time lag from the release. The authors find that, dependently on the given observable, the quasigeostrophic turbulence scenario is overall compatible with their data analysis, with discrepancies from the expected behavior of 2D turbulent trajectories likely to be ascribed to the nonstationary and nonhomogeneous characteristics of the flow, as well as to possible ageostrophic effects. Submesoscale features of similar to O(1) km are considered to play a role, to some extent, in determining the properties of relative dispersion as well as the shape of the energy spectrum. The authors also present numerical simulations of an ocean general circulation model (OGCM) of the South Atlantic and discuss the comparison between experimental and model data about mesoscale dispersion

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Since November 2015, two underwater gliders equipped with external hydrophones were deployed in the South Brazilian Bight in order characterize the area's soundscape. Contrasting to standard fixed mooring systems (where flow noise is generated by currents passing by the hydrophones), gliders are subject to noise generated by its own downward and upward motion, which may compromise soundscape characterizations if not properly evaluated. In order to investigate induced flow noise on the hydrophone and its characteristics, 563 hours of acoustic data from the gliders were correlated to the navigation settings. Results can be comparable to previous flow noise descriptions for fixed systems. A high correlation was observed between the glider speed (both vertical and total) and 1/3 octave band levels centered at frequencies below 20 Hz. Estimates of the broadband sound pressure level were accomplished with different lower frequency limits and found to be uncorrelated to the glider speed above 40 Hz.

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A crescente atividade humana vem produzindo cada vez mais resíduos sólidos, que geram problemas devido ao descarte inadequado e a poluição. No entanto, estes resíduos podem gerar através da decomposição biológica da matéria orgânica o biogás, uma mistura gasosa composta principalmente por gás metano ( CH4) , gás carbônico (CO2) e umidade. A pesquisa apresenta dados referentes à produção do biogás a partir da decomposição da matéria orgânica, com a proposta de produzir energia elétrica e posteriormente reaproveitar o resíduo orgânico como biofertilizante. Foi produzido um protótipo de reatores para a geração do biogás composto por tubos de Policloreto de Vinila (PVC), conectados a uma proveta de 1L e galões de 5L, se faz necessário a adição de uma quantidade proporcional de água como forma de mobilizar os resíduos ali presentes para produção eficaz do gás metano.  Através dos resultados obtidos nos experimentos pode - se verificar a produção do gás em determinadas quantidades de esterco e resíduo orgânico analisando sua eficiência nesse contexto. Mediante a análise feita, os resultados obtidos foram satisfatórios para a quantidade de matéria orgânica utilizada, sendo assim, o projeto pode ser construído em grande escala para geração de energia elétrica por meio de um conjunto moto-gerador, onde essa energia elétrica pode ser utilizada tanto em residências urbanas quanto em áreas rurais devido à quantidade de matéria-prima