Abstract The carbon derived from the thermal treatment of modified phenolic resins (PR) tends to organize into graphitic lamellae or turbostratic carbon and is commonly considered non-graphitizable. In this study, nanocomposites were synthesized with modified phenolic resin (Novolac) used as the matrix and oxidized multi-walled carbon nanotubes (NTox) in amounts ranging from 0.3 to 2.5 wt% as a filler. Thermal gravimetric analysis (TGA), Raman spectroscopy, powder X-ray diffraction (XRD), scanning electron microscopy (SEM) with field emission gun (FEG), and transmission electron microscopy (TEM) were performed. By TGA, the PR-2.5 wt% nanocomposite showed less thermal degradation and higher stability when compared to the pure matrix after heat treatment up to 1000 °C. Graphitic carbon organization analysis by Raman spectroscopy, XRD, SEM/FEG, and TEM micrographs showed that the PR-2.5 wt% nanocomposite is suitable for technological applications, involving a carbon graphitization tendency.

Industrial applications demand that robots operate in agreement with the position and orientation of their end effector. It is necessary to solve the kinematics inverse problem. This allows the displacement of the joints of the manipulator to be determined, to accomplish a given objective. Complete studies of dynamical control of joint robotics are also necessary. Initially, this article focuses on the implementation of numerical algorithms for the solution of the kinematics inverse problem and the modeling and simulation of dynamic systems. This is done using real time implementation. The modeling and simulation of dynamic systems are performed emphasizing off-line programming. In sequence, a complete study of the control strategies is carried out through the study of several elements of a robotic joint, such as: DC motor, inertia, and gearbox. Finally a trajectory generator, used as input for a generic group of joints, is developed and a proposal of the controller's implementation of joints, using EPLD development system, is presented.

First-principles calculations of electronic band structures of the ordered cubic alloys Al xGa1-xN and Cd xZn1-xTe are carried out. The band structures are used to provide e ective masses and Luttinger parameters which are useful in the parametrization of theories based on e ective hamiltonians.