A strong influence of microbial mats on the physics of Neoproterozoic sedimentation is explored within a 60 m-thick stratigraphic interval within the Sonia Sandstone, Jodhpur Group, western India. This marine interval is bounded by two terrestrial units, its base being marked by a transgressive lag and the top by an unconformity. Progradation from upper neritic, above fair-weather wave base to supralittoral settings was later terminated by a transgression; deposits of lower shoreface-upper shoreface transition thus overlie supralittoral aeolian sandstones, the basal contact of the former deposits being marked by another transgressive lag.A wide spectrum and abundant examples of microbial mat or mat-derived structures supports unusual cohesiveness within granular sand deposited in a high-energy marine environment. The cohesiveness is manifested in abundant preservation of several delicate primary structures and also in their replication in overlying beds, even after they were subjected to high-energy currents.A low rate of sedimentation and severely restricted sediment reworking resulted from prolific mat growth, and consequent depletion in the sediment budget was manifested in openUP (April 2008) bedform migration and evolution. These factors could also have influenced the sequencebuilding pattern in a distinctive way, as is already reported from several Meso-and Neoproterozoic successions. Ubiquitous mat growth thus had the potential to impart significant distinctions to Proterozoic clastic sedimentary successions.

Propylammonium lead iodide (C3H7NH3PbI3), a promising hybrid perovskite, is successfully synthesized by a solgel technique. Structural, optical, and dielectric properties have been studied in detail. The dielectric constant, loss factor, electric modulus, and AC and DC conductivity of this hybrid perovskite exhibit strong temperature dependence over the frequency range of 10 Hz ≤ f ≤ 8 MHz. The Nyquist plot reveals the distinct contributions of grain and grain boundary to the total impedance. The dielectric constant is found to increase with temperature in the high frequency region. The modified Cole–Cole plot shows that the space charge and free charge conductivity increase with the elevation of temperature, whereas the relaxation time decreases with the rise in temperature. From the modified Kohlrausch–Williams–Watts equation, we perceived asymmetrical nature in electric modulus spectra at various temperatures, which corresponds to the non-Debye type nature of perovskite. It has also been found that, with the elevation of temperature, the imaginary part of electric modulus spectra shifts from the non-Debye type toward the Debye type nature, though failing to acquire exact Debye type response, and emerges as a semiconductor material. AC conductivity of PAPbI3 is illustrated on the basis of the correlated barrier hopping (CBH) mechanism. Activation energy estimated from both modulus spectra and DC conductivity matches well, affirming the similarity between relaxation behavior and conduction mechanism. Along with all these, PAPbI3 possesses a high dielectric constant associated with a small dielectric loss, making it a potential candidate for energy harvesting devices.

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This work presents a comparative study of the morphology and structure-related properties of thermoplastic elastomer blends based on SEBS-PP-oil and dynamically vulcanized EPDM-PP-oil prepared under identical conditions. Compositions of each blend type with three different SEBS-PP and EPDM-PP ratios by weight were made in a co-rotating twin-screw extruder and a Brabender internal mixer. A comparative study of different electron microscopic techniques for studying the morphology of these oil-extended blends is reported. Morphological characterization using different microscopic techniques showed a co-continuous morphology for the SEBS-PP-oil blends and droplet-matrix morphology for the thermoplastic vulcanizate (TPV) blends. The particle size distribution of the EPDM-phases in the TPVs prepared in the twin-screw extruder was wider than for the Brabender mixer. No difference in the morphology was observed for the SEBS-PP-oil blends prepared in the twin-screw extruder and Brabender, except for the blend with the highest PP content. The elongation-at-break values were significantly higher for the SEBS-PP-oil blends as compared to the TPV blends. The gel content of the TPVs was the main factor determining the stress-strain properties, as influenced by the preparation method. Also the crystallinity of the PP-phase for both SEBS-PP-oil and TPV blends was investigated and, although being dependent on the preparation method for the SEBS-PP-oil blends, did not reflect in the stress-strain properties.