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The objective of this work was to evaluate the effect of soil cover species and management systems in improving the physical characteristics of a Haplortox and its effects on grain yield and soybean oil content. The experimental area, consisted of 15 treatments in a completely randomized experimental design. Each plot had size of 20 × 25 m. The treatments consisted of: traditional no-tillage system (control), no-tillage system with application of gypsum, no-tillage with scarification and 12 treatments with cover species called soil structure reclaimers. Soil samples were collected in the layers of 0-0.10; 0.10-0.20 and 0.20-0.30 m, with four replicates. The physical attributes evaluated were bulk density, total porosity, microporosity, macroporosity and saturated hydraulic conductivity in the periods of 2014, 2015 and 2016. In the soybean crop the grain yield, oil content, weight of 100 grains, average height of plants and number of plants/m were evaluated in each treatment with four replications. The oil content was performed by the low-field nuclear magnetic resonance method. The averages of the treatments were compared by the Tukey test at 5% of significance. The results showed that five months after soil scarification did not affect bulk density. Eleven months after gypsum application discrete improvements in density, total porosity, microporosity and soil hydraulic conductivity occurred in the 0-0.10 and 0.10-0.20 m layers. It was also concluded that grain yield, oil content, weight of 100 grains and number of plants per meter were not influenced by the soil cover species and soil management systems.

Based on the observation of the effects of energy generation on climate change, efforts have been carried out to develop technologies to reduce polluting energy sources. In this context, the rational use and improvement of the efficiency of water heating systems can play an important role, contributing to lower energy consumption. This study evaluated a prototype for water heating for use in agroindustry. The prototype was designed for a possible utilization of mechanical energy in order to change the magnetic flux produced by permanent magnets, generating thermal energy by Foucault currents. This system presented yields of 64.74%, 65.13% and 64.48% for the rotor configurations with six magnets without pole reversal (6ISI), four magnets with reversal (4ICI), and four magnets without reversal (4ISI), respectively. For comparison purposes, a resistive water heating system was also evaluated for the same study conditions, obtaining an efficiency of 89.21%. The proposed inductive system did not present satisfactory results for constructive conditions presented in the study.