DC Conductivity in P-Toluenesulphonic Acid Doped Poly (2-Methylaniline)

Para-toluenesulphonic acid doped Poly(2-methylaniline) (PmANI) was synthesized by chemical method using ammoniumpersulphate (APS) as an oxidant. It was synthesized along with optimization studies w.r.t. varied dopant-monomer ratios for better DC conductivity. Various spectroscopies like XRD, UV-Vis and FT-IR were used to characterize the polymer. The behavior of DC conductivity with variation in temperature was studied with in the temperature range of 300 - 425 K and it was observed that conductivity rised to ~four orders with the surge in temperature. The experimental conductivity data was fitted with various conduction models to find the proper charge transport mechanism in this polymer.

Study of Electrical Conductivity in WO3-doped Nonstoichiometric LiTaO3

The results of experimental and analytical studies of the electrical conductivity for different solid solutions synthesized in a vicinity of LiTaO3 in the ternary system Li2O–Ta2O5–(WO3)2 are presented. It is shown that the electrical conductivity increases linearly with the Curie temperature. The experimental conductivity between 200 and 700 ºC was measured using an LCR bridge HP4192A on ceramics sintered at 1250 ºC. Within the theoretical approach to the defect structure analysis combined with our proposed vacancy models, the theoretical results are in a good agreement with the experimental data.

CONDUCTOMETRIC EVALUATION OF ASSOCIATION CONSTANTS FOR AQUEOUS SOLUTIONS OF CoCl2 IN THE ABSENCE AND PRESENCE OF A MAGNETIC FIELD

The association constants KA for CoCl2 aqueous solutions were calculated using the experimental conductivity values at different salt concentrations. The molar conductivities were measured in the absence and presence of a magnetic field with an average power of 0. 677 KGauss. A new equation for asymmetric 1:2 salts was suggested and used. This equation was derived from Ostwald, Arrhenius, and Fuoss-Shedlovsky theories. The results obtained were discussed and the effect of the magnetic field on the association constants was explained.

Solid Electrolytes: Microstructural Characterization by Conductivity Spectroscopy

ABSTRACTIn conductivity spectroscopy, ionic conductivities of solid electrolytes are measured continuously from a few Hertz up to the mid-infrared, i.e., in a frequency range covering more than twelve decades. In this paper we present experimental conductivity spectra of various cryst alline and glassy ionic conductors. Tracing the characteristic patterns of the spectra back to their generic processes provides a powerful means for probing the motion of the ions on atomic scales of space and time. The technique is particularly useful for exploring the single-particle potentials felt by the ions and, hence, for elucidating details of the surrounding structure. In our examples we discuss widths, anisotropies, and geometrical arrangements of sites in crystals as well as the existence of non-equivalent sites in glass.

Electrical Conductivity of a Semidilute Polyelectrolyte in Mixed Solvent Media

The electrical conductivity of solutions of sodium salt of polystyrenesulfonate in methanol-water mixed solvent media containing 8, 16, 25, and 34 weight per cent of methanol at 308.15, 313.15, 318.15 and 323.15 K was studied earlier. In that report, an attempt was made to interprete the results using the Manning Counterion Condensation Theory. Unfortunately, a major deviation of the theoretical prediction from the experimental results was noticed and the possible reasons for this discrepancy have been discussed. In this communication, the experimental conductivity have been analyzed on the basis of a new model for semi-dilute polyelectrolyte conductivity which takes into electrical conductivity of semidilute solutions of polyelectrolytes without added salt has been recently described by Colby et al. (1997) using the scaling description proposed by Dobrynin et al. (1995) for the configuration of a polyelectrolyte chain in semi-dilute solution. The predictions are found to be compared favorably well with the observed conductivity over the whole range of concentrations investigated. Key Words: conductivity; counterion; condensation; semi-dilute; Manning theory DOI: 10.3126/njst.v9i0.3182 Nepal Journal of Science and Technology 9 (2008) 163-170