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Despite the huge potential, integral passives form less than 3% of the replaceable discrete components. A major obstacle in bridging this gap has been the absence of a wider choice of materials that would conform to stringent performance requirements. Epoxy-ceramic composite dielectrics have been investigated in recent time towards the fabrication of integral thin film capacitors due to their compatibility with processing conditions for printed wire boards (PWB). Though many investigations in recent past have focussed on the dielectric properties of epoxy-ceramic composites it is surprising that investigations on the interfacial effects did not receive the attention they deserve.These effects are even more pronounced in nanocomposites as the influence of the interface turns dominant with decreasing size of the dispersed ceramic phase. Functionalization of barium titanate (BTO) nanoparticles with an organic silane was shown to improve the dispel-sion of the particles in the epoxy matrix and hence the rheological properties. The dielectric properties of a nanocomposite with a surface modified ceramic dispersant are likely intluenced in two ways (a) change in the microstructure of the composite brought about by the improved dispersibility and (b) change in the interfacial or Maxwell-Wagner-Sillars (MWS) polarization in the heterogeneous phase. Fundamental understanding of such intluences is important in the design of polymerinorganic nanocomposites.These intluences were investigated in the case of epoxy as well as polyvinylidene fluoride (PVDF) matrices with a dispersion of barium titanate nanoparticles at different volume fractions. Dielectric properties such as relative permittivity and impedance were investigated with frequencies up to IO7 Hz. The organic inodification of the interface was found to significantly intluence the processibility and dielectric properties.

Effects of strontium doping on electrical properties of gadolinium-doped ceria were investigated. The Ce 0.8−x Gd 0.2 Sr x O 2−δ (0.0 ≤ x ≤ 0.1) compositions were prepared by sol-gel method and sintered at 1300• C for 8 h, the bulk densities were over 93% of theoretical density. These results were consistent with scanning electron microscope. The crystallite size of these materials was determined using the X-ray powder diffractometer and the sizes range from 19.4 nm to 24.4 nm. From the experimental results, it was observed that the composition Ce 0.8−x Gd 0.2 Sr x O 2−δ (x = 0.02) exhibits higher conductivity (23.6 × 10 −3 S cm −1 ) and minimum activation energy (0.83 eV) at 700• C. This composition is thus a potential candidate for use as electrolyte applications in intermediate temperature solid oxide fuel cells.

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An ecofriendly and environmentally benign asymmetric reduction of various prochiral ketones employing soaked Phaseolus aureus L as a biocatalyst was developed. We found for the first time that the soaked Phaseolus aureus L (commonly called green grams in India) could be effectively used for enantioselective bioreduction. This process is more efficient and generates less waste than the conventional chemical reagents or microorganisms. This process has been successfully tested for multigram scale production of optically active alcohols and this approach is found to be the most suitable for the preparation of pharmaceutically important molecules.

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