Jai Narain Vyas University

Solar energy is a never-ending energy source.There are many solar techniques for converting the solar energy into elec. energy.Among them, the photo-galvanic cell (PG) is a solar energy technique, which also enables power storage.For the fabrication of the PG cells, a combination of the reductant-surfactant-dye sensitizer- alkali is used.An alkali is the main fabrication component of photo-galvanic cell for solar power generation.For effective working of the PG cells, the ideal electrolyte should have the alkali with capacity of being dissociated completely.The higher dissociation of alkali leads to the higher value of the pH of the electrolyte.Because of this, the nature of the alkali holds the key importance for the efficient working of the PG cells.The effective working of the PG cells requires higher value of the pH of the electrolyte.This higher value of the pH favors the efficiency of the PG cells.In the present research, different alkali materials (i.e., NaOH, KOH, Ca (OH)₂, NaHCO₃, and spinach extract) have been studied in the transparent H-Cell design to find out the relatively most suitable alkali material.The cell power output for various alkali materials (with pH of electrolyte), for example, NaOH (pH 13.94), KOH (pH 14.30), Ca (OH)₂ (pH 11.95), NaHCO₃ (pH 8.12), and spinach extract (pH 6.00) is 806, 283.8, 0.512, 0.220, and 0.320 μW, resp.Under exptl. conditions, it is observed that the NaOH alkali material is relatively more efficient and suitable alkali material for solar energy conversion and storage through the PG cell.The observations of the present study are also supported by the already published work.

Abstract: Orthosilicate compounds are the olivine structured transition-metal silicates, which are technol. established in the advances of luminescent and spintronic devices, and electrode materials for lithium ion batteries.In the present study, cobalt orthosilicate compound Co₂SiO₄ was synthesized through solid state reaction process by sintering the powder at 1170 °C for 8 h.A comprehensive anal. of powder X-ray diffraction data showed that the compound crystallizes in the Pbnm space group of orthorhombic symmetry with cobalt atoms in octahedral and silicon atoms in tetrahedral environments.Fourier transform IR bands and Raman mode analyses further confirm the formation of this compound in orthorhombic structure.Morphol. and elemental anal. substantiate the right stoichiometry of the synthesized Co₂SiO₄ material.The dielec. constant and loss angle tangent spectra in the broader frequency range of 10¹ to 10⁹ Hz show the fundamental polarization trend of dielec. ceramics.The electronic transitions observed in the visible region of the UV-Vis reflectance spectrum correspond to the d-d transition of Co²⁺ ions in octahedral crystallog. arrangement.The photoluminescence spectroscopic anal. and the CIE coordinates suggest that the blue-violet emission from the Co₂SiO₄ compound could be useful for development of advanced luminescent devices.Magnetic measurements showed paramagnetic features of this compound at room temperature together with a transition from paramagnetic to antiferromagnetic at 50 K, superimposed with weak ferromagnetism.A low temperature (10 K) magnetic hysteresis explains weak ferromagnetic like behavior of the Co₂SiO₄ compound arising from uncompensated surface spins.The neg. Weiss temperature value of about - 59 K substantiates the strong antiferromagnetic exchange interactions.The effective paramagnetic moment 3.89μ_B is found close to the spin only value 3.87μ_B of Co²⁺ ion (S = 3/2).

Abstract: Background and aims: Root nodule microsymbionts of native Prosopis cineraria and three exotic species of Neltuma (formerly Prosopis), N. juliflora, N. alba and N. pallida, were trapped from soils of different agro-climatic regions of India to analyze preferences of host plants towards their microsymbionts.Methods: Ability of Prosopis/Neltuma species to nodulate in alk. to acidic soils was determined through trap experimentsNodule anatomy was examined using light and transmission electron microscopy.Symbionts were genetically characterized using multi locus gene sequence-based phylogenies of core and symbiotic genes.Host range was confirmed through cross-inoculation experimentsResults: Nodules of Prosopis and Neltuma species are of the mimosoid type with genetically diverse strains of Ensifer/Sinorhizobium, Mesorhizobium, Bradyrhizobium and Rhizobium as their microsymbionts.Only P. cineraria nodulated in acidic soils of Meghalaya wherein it adopted Bradyrhizobium as symbionts.In addition to large variability based on core genes, substantial diversity was observed in the nodA genes harbored by Sinorhizobium with clear incidences of horizontal gene transfer; several Sinorhizobium strains harbored dominant and typical "Indian mimosoid clade" nodA genes.Sinorhizobium is the dominant symbiont of Prosopis/Neltuma species and cross nodulates related Indian native mimosoids such as Mimosa himalayana and species of Vachellia.Conclusion: Overlaps were seen in symbionts isolated from the native and exotic species suggesting that these hosts are open and inclusive towards a wide range of symbionts irresp. of their origin.Most tree rhizobia were incompatible with herbaceous papilionoid legumes.Invasive mesquites are assisted in their invasiveness by their ability to nodulate with native rhizobia.