Abstract Microgrids have been widely applied to improve the energy quality parameters of a distribution system locally, in addition to ensuring the operation of the system in an isolated manner. The Model Predictive Control (MPC) is a great solution to guarantee the operation of the system considering forecasting models and also physical restrictions of the system, which ensure the optimal operation of the Microgrid. However, the construction of a control scheme following the objectives established in order to meet the connected and isolated operation of a Microgrid is still a challenge. This paper proposes the development of an MPC control scheme that assures optimal system operation in connected and islanded mode, improving power quality indexes, ensuring network requirements, and extending battery life cycle. The proposed control operation in the connected mode can attend to the needs of the Microgrid, reducing the impacts of peak demand and the intermittent variations in renewable generation, where a linear objective function is developed for this purpose. In the islanded mode, grid requirements are guaranteed through load shedding, considering improvements in continuity indicators. Forecasting models are implemented considering the MPC approach and a detailed network model is developed. Simulation results highlight the effectiveness of the proposed control strategy.

We present here our results on the temperature controlled, selective hydrochalcogenation of 1,4-diorganyl-1,3-butadiynes with nucleophilic species of selenium, tellurium and sulfur generated in situ from the respective diaryl dichalcogenide and NaBH4. Using polyethylene glycol (PEG)-400 at 30 ºC the (Z)-chalcogenoenynes are obtained and at 90 ºC the (Z,Z)-bis-chalcogen-1,3-butadienes are produced in good to excellent yields. Alternatively to conventional oil bath heating, the use of microwave irradiation is also presented as an alternative energy source that provides the expected products in few minutes.

We present here our results in the synthesis of eleven new 3-(1H-1,2,3-triazol-1-yl)-2-(arylselanyl)pyridines by copper-catalyzed azide-alkyne cycloaddition reactions. The reactions were performed in the presence of catalytic amount of copper(II) acetate and sodium ascorbate using a mixture of tetrahydrofuran/water (1:1) as solvent at room temperature in air. The reaction is tolerant to different functional groups such as substituted-benzene rings, alcohol and ester and none electronic or steric influence was observed. All the products were obtained in good to excellent yields. Alternatively to the conventional oil bath heating, the use of microwave irradiation or ultrasound methods is also presented as alternative energy sources.

Este trabalho descreve nossos resultados para a reação entre benzenosselenol, gerado in situ pela reação entre disseleneto de difenila com H3PO2, com uma série de (E)-chalconas utilizando glicerol como solvente. Utilizando as condições de reação otimizadas, uma variedade de produtos de redução 1,4-quimiosseletivas podem ser obtidos em bons rendimentos. A mistura glicerol/H3PO2 pode ser facilmente recuperada e reutilizada em condições de reação de redução 1,4-quimiosseletivas por ciclos sucessivos sem perda de eficiência. Adicionalmente, sob condições de reação de redução 1,4-quimiosseletivas, o produto natural zingerona pode ser sintetizada em bom rendimento.

We describe herein our results for the reaction of benzeneselenol, generated in situ by reaction of diphenyl diselenide with H3PO2, with various (E)-chalcones using glycerol as solvent. Using our optimized reaction conditions, a range of chemoselective 1,4-reduction products could be obtained in good yields. The glycerol/H3PO2 system can be easily recovered and reused in chemoselective 1,4-reductions for successive cycles without loss of efficiency. Additionally, under 1,4-reducing reaction conditions, the natural product zingerone can be synthesized in good yield.