The dielectric properties (the relative permittivity and the dielectric loss) of the layer structure perovskites (CH2)6(NH3)2MCl4 (M = Mn, Co, Cu and Ni) are investigated in the frequency range 1 kHz-1 MHz and in the temperature range - 150 to 210°C. One relaxation peak for Mn and Cu complexes and three relaxation peaks for Co and Cu complexes are observed. The results of IR and DSC for the complexes are also given.

D.C. electrical resistivity, dielectric constant and dielectric loss tangent of ethylene diamene tetrachloride metal complexes have been studied covering all transition points. Both temperature and ionic radii of metals played an effective role in the electrical transport processes. The dielectric loss tangent behaviour exhibits two relaxation peaks for ligand matrix at 328 and 407 K. The lower-temperature relaxation peak is interpreted in terms of small-scale movements of the dipole groups.

The oxidation of perphenazine to perphenazine sulphoxide by peroxyacetic acid was kinetically studied utilizing first-derivative UV-spectrophotometry and a simple iodometric procedure. The first-derivative UV-spectrophotometric procedure indicates that the reaction with respect to perphenazine is most probably zero-order at the initial stage with a rate constant (k0) of magnitude 5.62 x 10-8 mol L-1 S-1. Based on the titrimetric procedure in which 0.01 N Na2S2O3 was employed, the reaction with respect to peroxyacetic acid is most probably second order initially having a rule constant (k2) equal to 0.05805 L mol-1 S-1. The disparity between the orders with respect to concentration (i.e. n(c)) and time (i.e. n(t)) for peroxyacetic acid was highlighted.

The protective effect of honeybee aqueous propolis extract (APE) against the hepatotoxicity of carbon tetrachloride was investigated using isolated liver-cell suspensions as the experimental model. Various concentrations of the extract were preincubated with the hepatocyte suspensions for 30 min before being subjected to the hepatotoxin for a further 30 min. The hepatocyte toxicity was assessed using three parameters, namely, the release of lactate dehydrogenase, the formation of lipid peroxides and the depletion of intracellular reduced glutathione. It was found that a dose-related protection against the induced cell injury was conferred by APE as evidenced by its inhibitory influence on the changes induced by CCl4 on the measured parameters. The hepatocyte protective effect of APE is probably a result of its antioxidant and free-radical-scavenging properties which in turn help to maintain the intracellular level of reduced glutathione.

The protective effect of honeybee aqueous propolis extract (APE) against the hepatotoxicity of carbon tetrachloride was investigated using isolated liver-cell suspensions as the experimental model. Various concentrations of the extract were preincubated with the hepatocyte suspensions for 30 min before being subjected to the hepatotoxin for a further 30 min. The hepatocyte toxicity was assessed using three parameters, namely, the release of lactate dehydrogenase, the formation of lipid peroxides and the depletion of intracellular reduced glutathione. It was found that a dose-related protection against the induced cell injury was conferred by APE as evidenced by its inhibitory influence on the changes induced by CCl4 on the measured parameters. The hepatocyte protective effect of APE is probably a result of its antioxidant and free-radical-scavenging properties which in turn help to maintain the intracellular level of reduced glutathione.

Dielectric results at frequencies between 0.1 and 100 kHz throughout temperature range of 150-450 K are given for the natural Egyptian monazite. Three distincit absorption peaks (γ, β, and α) are observed in order of increasing temperature. Displacement toward high temperatures of the three relaxations with increasing frequencies is justified. The Cole-Cole diagrams have been used to determine the molecular relaxation time T the activation energy of the β-relaxation. The A.C. conductivity is found to be proportional to ωS(T). The high value of A.C. conductivity compared with the D.C. conductivity indicates the dominance of the dipole polarization mechanism.