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The polycrystalline material Sr(Bi3.9-xNdxLa0.1)(Ti3.975Zr0.025)O15 with variation of neodymium content from 2.5 to 10 wt% was prepared by solid state method. XRD analysis indicated the formation of a single- phase orthorhombic structure. SEM analysis revealed the formation of plate like structure. It was also observed that with increase in the content of Nd, the values of Curie temperature (Tc) and dielectric constant (ε) were increased and the tolerance factor (t) decreased. It was found that the remnant polarization, piezoelectric charge and electromechanical coupling coefficients were increased up to certain extent of Nd doping and further increase of Nd content decreased. [ABSTRACT FROM AUTHOR]

In this article, we report advancement in structural, morphological and dielectric studies of PVA encapsulated titanium dioxide (TiO2) and zinc oxide (ZnO) nanoparticles. PVA/(x)TiO2(15-x)ZnO nanocomposites are prepared using solvent casting ex-situ technique for x= 0wt%, 1wt%, 5wt%, 7.5wt%, 10wt%, 14wt% and 15wt% filling concentrations. FTIR spectroscopy reveals the formulation of complexes between the PVA main chain and nano fillers is due to inter/intra molecular hydrogen bonding. The AFM picture shows the uniform grain structure for pure PVA and changes in surface morphology for prepared PVA nanocomposites. The morphological and homogeneous distribution of nano fillers in PVA nanocomposites was observed using SEM and EDAX. AC conductivity studies spectacles that the conductivity increases for different filling concentrations with increase in frequency. The frequency dependent dielectric constants with different filling concentrations are recorded. [ABSTRACT FROM AUTHOR]

The composition of Anthracene and Lead Titanate is prepared using Solid State reaction method. Anthracene is a solid polycyclic aromatic hydrocarbon (PAH) of formula C14H10, consisting of three fused benzene rings. It is a component of coal tar. Lead (II) titanate is an inorganic compound with the chemical formula PbTiO3. It is the lead salt of titanic acid. Lead (II) Titanate is a yellow powder that is insoluble in water. At high temperatures, lead Titanate adopts a cubic perovskite structure. The samples of Anthracene Lead Titanate composites of suitable mixture ratio are prepared using Solid state reaction method. The Crystal structure of the calcined powders and also sintered ceramics were analyzed using XRD (X-ray diffraction). The microstructure of the sintered ceramics has been investigated by using SEM (Scanning Electron Microscopy).The dielectric constants were calculated for different mixture ratios and at different temperatures are reported in this paper. It was observed that an increase in temperature there is a change in the dielectric constants has also been reported in this paper. It observed that the dielectric constant increasing with temperature increases. [ABSTRACT FROM AUTHOR]

The polymer blend composites of PANI with PVDF/KDP have been synthesized by polymerization method. The different polymer blend of PANI with PVDF/KDP composites are obtained by adding 10, 20, 30, 40 and 50 wt% of KDP were added with PVDF of 1N concentration during PANI synthesis to get the polymer blend of PANI with PVDF/KDP composites. The synthesized samples of PANI and polymer blend of PANI with PVDF/KDP composites polymer were characterized by using X-Ray diffraction (XRD). The dielectric properties such as dielectric constant, dielectric loss and AC conductivity for the composites of polymer blend of PANI with PVDF/KDP composites at different weight percentages are studied as a function of frequency in the range 5 Hz–35 MHz at room temperature. It is found that the dielectric permittivity decreased exponentially at lower frequency region up to 180 Hz and then the dielectric permittivity remains constant at higher frequency region as the frequency increased. It is also observed that the dielectric permittivity decreased as the weight percentages of KDP increases in PVDF with PANI. AC conductivity increased for PANI, polymer blend of PANI with PVDF/KDP composites at 10, 20, 30 and but for 40 and 50 wt% it is decreased. [ABSTRACT FROM AUTHOR]

The 0.85(Na0.41K0.09Bi0.5TiO3) –0.15(CoFe2O4) or x(NKBT)- (1-x) CFO where, (x=15 wt %) particulate composite was successfully synthesized by conventional solid state sintering method. The structural and microstructural studies confirmed the formation of hybrid composite. NKBT-CFO composite showed polarization vs electric field at room temperature. The dielectric constant value found ≅4734 at 330 °C at 100 kHz frequency, which is higher than pure NKBT. The Kp value for a poled sample was measured is ∼16.7% at room temperature. Magnetoelectric coupling study had been done by measuring magneto-capacitance and polarization vs electric field measurement before and after magnetic poling for up to 1 Tesla in an external magnetic field. [ABSTRACT FROM AUTHOR]

Glass samples with composition (50 - X) PbO - (25 + X) TiO2 - 25 B2O3 (where X =0, 5, 10 and 12.5 mol %) were prepared using conventional quenching technique. These glass samples were converted to glass ceramics by following two stage heat treatment schedules. Transition temperature (Tg), crystallization temperature (Tc), density and Coefficient of Thermal Expansion (CTE) of glass and glass ceramic samples measured. Tg and Tc observed to decrease with increase in the content of TiO2. The density values of glass ceramic samples are higher than those of corresponding glass samples. It was observed that there was good correlation between the density and CTE results of the glass–ceramics. The dielectric constant of glass ceramic samples is higher than those of corresponding glasses. Maxwell’s dielectric mixture formula was used to correlate the theoretically predicted values of dielectric constant with experimentally observed values. [ABSTRACT FROM AUTHOR]