Air conditioning systems represent one of the main demands for electricity in residential, commercial and industrial buildings. The use of a photovoltaic air conditioning unit (PVACU) represents an attractive application to this demand for reasons such as environmental concerns and the match between diurnal cooling load and solar resource. A PVACU consists of a photovoltaic generator (PVG) that supply an air conditioning system (ACS) through DC-DC and frequency converters, without energy storage. This system considers the natural adjustment of the ACS cooling capacity according to the PVG power. Modelling the ACS, the PVG and the thermal load (TL) makes possible to evaluate PVACU performance. For this, a small library's TL and an ACS supplied by a PVG were used as case study. The PVG installed capacity assumes values of 700, 1000 and 1400 Wp. The simulation results show that the PVACU with a 1400 Wp PVG would be sufficient to regulate internal temperature within international comfort standards in the range of 20 °C to 24 °C. According to the data obtained in the simulations, it was possible to conclude that the PVACU has a large potential to be used in air conditioning of other environments in regions with Amazonian climatic conditions.

Here we analyzed several physical behaviors through computational simulation of systems consisting of a zig-zag type carbon nanotube and relaxed cold atoms (Rb, Au, Si and Ar). These atoms were chosen due to their different chemical properties. The atoms individually were relaxed on the outside of the nanotube during the simulations. Each system was found under the influence of a uniform electric field parallel to the carbon nanotube and under the thermal effect of the initial temperature at the simulations. Because of the electric field, the cold atoms orbited the carbon nanotube while increasing the initial temperature allowed the variation of the radius of the orbiting atoms. We calculated the following quantities: kinetic energy, potential energy and total energy and in situ temperature, molar entropy variation and average radius of the orbit of the atoms. Our data suggest that only the action of electric field is enough to generate the attractive potential and this system could be used as a selected atoms sensor.

Piezoelectric material has the property of converting energy from the mechanical pressure of an external body into electrical energy on the piezo-structure, providing a strong potential source for renewable energy. Our aim in this article is to explore the properties of polyvinylidene fluoride polymer under the influence of an electric field. In sense to understand the behavior of integer polymer, we started to simulate the optimization of several small sizes (monomer, dimmer, trimer and tetramer) of this polymers subjected to uniform electric fields in the direction of the electric dipole applying a external electric field and analyzing the displacement of electrical charges. For this optimization of this polymer we used PM3 semi-empirical methods applying electric field applications. These results elucidate the behavior of electrical charges of an organic piezoelectric material under the action of external and uniform electric field.

We propose a system that avoids the open ends of the nanotube, we used a device consisting of a flagellum in a torus formed by carbon atoms. The flagellum consists of a nanosphere C20 with fixed length of tail composed of three carbon atoms (FLA3) in the carbon torus (CT). The simulations were done by well-known classic molecular dynamics with standard parameterization. We calculated the thermodynamic properties of these devices such as heat capacity and molar entropy variation. For this system were obtained properties, such as the speed of nanospheres plagued the efficiency of molecular motor versus time, the kinetic energy, potential energy and total energy in each of the simulations. In our calculations, this system has a number of carbon atoms in 2723 with a maximum time of 10 ps for each simulation. These facts can be useful for the construction of new molecular machines.

We propose a system that avoids the open ends of the nanotube, we used a device consisting of flagellum (FLA) inside a nanotorus (NT) formed by carbon atoms. The flagellum consists of a C20 nanosphere with fixed size of tail within the NT. The full system consists of a closed loop drive and static nanotubes and nanospheres not static with different sizes of flagella released inside the nanotube, with each simulation, allows the relaxation between (internal and external NT). The nanospheres result in a system that provides movement of Van der Waals. The simulations were done by well-known classic molecular dynamics with standard parameterization. We calculate thermodynamic properties of these devices as heat capacity and molar entropy variation. For this system were obtained properties such as: the speed of nanospheres plagued the efficiency of molecular motor versus time, the kinetic energy, potential energy and total energy in each of the simulations. In our calculations, this system has a number of carbon atoms ranging from (2721 until 2728) with up to almost 10 ps simulation. These facts can be useful for the construction of new molecular machines.