Thomas P, Zachariah; Dr.Abdul Rasheed, T M(Cochin University of Science & Technology, March , 2008)
[+]
[-]
Abstract:
In the present study, radio frequency plasma polymerization technique
is used to prepare thin films of polyaniline, polypyrrole, poly N-methyl pyrrole
and polythiophene. The thermal characterization of these films is carried out
using transverse probe beam deflection method. Electrical conductivity and
band gaps are also determined. The effect of iodine doping on electrical
conductivity and the rate of heat diffusion is explored.Bulk samples of poyaniline and polypyrrole in powder form are
synthesized by chemical route. Open photoacoustic cell configuration is
employed for the thermal characterization of these samples. The effect of acid
doping on heat diffusion in these bulk samples of polyaniline is also
investigated. The variation of electrical conductivity of doped polyaniline and
polypyrrole with temperature is also studied for drawing conclusion on the nature of conduction in these samples. In order to improve the processability
of polyaniline and polypyrrole, these polymers are incorporated into a host
matrix of poly vinyl chloride. Measurements of thermal diffusivity and
electrical conductivity of these samples are carried out to investigate the
variation of these quantities as a function of the content of polyvinyl chloride.
Description:
Department of Physics,
Cochin University of Science and Technology
Parvathi, R; Indic, P; Nampoori, V P N(Elsevier, February 11, 2002)
[+]
[-]
Abstract:
Nonlinear time series analysis is employed to study the complex behaviour exhibited by a coupled pair of Rossler systems. Dimensional analysis with emphasis on the topological correlation dimension and the Kolmogorov entropy of the system is carried out in the coupling parameter space. The regime of phase synchronization is identified and the extent of synchronization between the systems constituting the coupled system is quantified by the phase synchronization index. The effect of noise on the coupling between the systems is also investigated. An exhaustive study of the topological, dynamical and synchronization properties of the nonlinear system under consideration in its characteristic parameter space is attempted.