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The potential of the environment to yield organisms that can produce functional bionanominerals is demonstrated by selenium-tolerant, aerobic bacteria isolated from a seleniferous rhizosphere soil. An isolate, NS3, was identified as a Bacillus species (EU573774.1) based on morphological and 16S rRNA characterization. This strain reduced Se(IV) under aerobic conditions to produce amorphous alpha Se(0) nanospheres. A room-temperature washing treatment was then employed to remove the biomass and resulted in the production of clusters of hexagonal Se(0) nano-rods. The Se(0) nanominerals were analyzed using electron microscopy and X-ray diffraction techniques. This Bacillus isolate has the potential to be used both in the neutralizing of toxic Se(IV) anions in the environment and in the environmentally friendly manufacture of nanomaterials.

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We present the results based on the electrooptic and dielectric studies in cadmium sulphide (CdS) nanorods/ferroelectric liquid crystal mixtures. Doping of CdS nanorods increases the spontaneous polarization and response time, which due to large dipole-dipole interaction and increase in anchoring energies exists between nanorods and FLC molecules. Dielectric measurements revealed a decrease (~40% for 0.3% CdS in FLC) in permittivity and dielectric strength in doped sample cell than pure FLC mixture. A decrease in dc conductivity and relaxation frequency with doping concentration was also noticed. The preexponent factor and fractional exponent factor are found as predicated by existing theories.

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Polarization switching and dielectric relaxations have been investigated in two novel ferroelectric liquid crystal mixtures. The samples of helical pitch ∼12 µm and 0.43 µm respectively were sandwiched in planar cells of 5 µm thickness. P S, τr and γ have been evaluated using polarization reversal current technique. Dielectric relaxation modes have been studied under different bias conditions. In volume stabilized cell configuration (p 0 ≪d) bulk domain mode appears due to the formation of modulated domain structures in bulk region while in surface stabilized cell configuration (p 0 ≫d) surface stabilized domain mode was observed. New relaxation mode appeared at all bias fields in SmC* phase due to the surface effects.