(C) 2011 American Institute of Physics. [doi:10.1063/1.3544482]“
“Composites of polyethylene oxide (PEO) filled with carbon nanofiber (CNF) were prepared using solution mixing followed by melt mixing. The morphology and thermophysical

properties of these composites and of pristine polyethylene oxide were analyzed by scanning electron microscopy, differential scanning calorimetry, thermogravimetric analysis, and dynamical mechanical analysis. Crystallization kinetic data were analyzed within the Avrami approximation for the primary stage of crystallization. The influence of CNF on the temperature dependence crystallization of PEO and the tendency of forming three-dimensional crystallites at higher crystallization temperature were observed. The nucleation features of CNFs dispersed within PEO were investigated by using Lauritzen-Hoffman Tariquidar ic50 nucleation theory. Crystallization activation energies were also computed; the results are in agreement with the Lauritzen-Hoffman theory. Thermogravimetric analysis and dynamical mechanical analysis showed a gradual increase of the thermal stability and of the storage modulus of the polymeric matrix due to the loading with CNFs and formation IGF-1R inhibitor of a polymer-carbon nanofiber interface. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011″
“This paper presents a technique for

improving the convergence rate of a generalized minimum residual (GMRES) algorithm applied for the solution of a algebraic system produced by the discretization of an electrodynamic problem with a tensorial electrical conductivity. The electrodynamic solver considered in this work is click here a part of a magnetohydrodynamic (MHD) code in the low magnetic Reynolds number approximation. The code has been developed for the analysis of MHD interaction during the re-entry phase of a space vehicle. This application is a promising technique intensively investigated for the shock mitigation

and the vehicle control in the higher layers of a planetary atmosphere. The medium in the considered application is a low density plasma, characterized by a tensorial conductivity. This is a result of the behavior of the free electric charges, which tend to drift in a direction perpendicular both to the electric field and to the magnetic field. In the given approximation, the electrodynamics is described by an elliptical partial differential equation, which is solved by means of a finite element approach. The linear system obtained by discretizing the problem is solved by means of a GMRES iterative method with an incomplete LU factorization threshold preconditioning. The convergence of the solver appears to be strongly affected by the tensorial characteristic of the conductivity.