A Molecular Dynamics of Cold Neutral Atoms Captured by Carbon Nanotube Under Electric Field and Thermal Effect as a Selective Atoms Sensor.

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.

Flagella interacting with a carbon nanowire with the variation of time and initial temperature.

The system proposed consists of a flagellum relaxing around a static carbon nanowire to mimics behavior of a natural flagellum moving with damped harmonic motion along a wire under van der Waals and electrostatic forces. This flagellum is composed of a C20 nanosphere with different sizes of his tail formed by hydrocarbons. The thermodynamic properties such as molar entropy variation, as well as molar heat dissipation, efficiency and speed were obtained to evaluate which system is most stable by using the variable temperature. This system has a number of carbon atoms ranging from 103-110, with a maximum of 300 ps for each simulation. We had simulated molar entropy variation, energies and efficiency changing with time and initial temperature. The results indicate that among the systems studied, the flagellum with five carbon atoms achieved greater stability and better results in this search.

Molecular dynamics study of the flagella inside the carbon torus.

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.