In this article we present a class of relativistic solutions describing spherically symmetric and static anisotropic stars in hydrostatic equilibrium. For this purpose, we consider a particularized metric potential, namely, Buchdahl ansatz [Phys. Rev. D 116, 1027(1959.] which encompasses almost all the known analytic solution to the spherically symmetric, static Einstein field equations(EFEs) with a perfect fluid source, including in particular the Vaidya-Tikekar and Finch-Skea. We here developed the model by considering anisotropic spherically symmetric static general relativistic configuration that plays a significant effect on the structure and properties of stellar objects. We have considered eight different cases for generalized Buchdahl dimensionless parameter K, and analyzed them in an uniform manner. As a result it turns out that all the considered cases are valid at every point in the interior spacetime. In addition to this, we show that the model satisfies all the energy conditions and maintain hydrostatic equilibrium equation. In the frame work of anisotropic hypothesis, we consider analogue objects with similar mass and radii such as LMC X-4, SMC X-1, EXO 1785-248 etc to restrict the model parameter arbitrariness. Also, establishing a relation between pressure and density in the form of P = P (ρ), we demonstrate that EoSs can be approximated to a linear function of density. Despite the simplicity of this model, the obtained results are satisfactory.

The results show the potential of the large eddy simulation as a high-quality comparative case to check the suitability of a chosen Reynolds-averaged Navier-Stokes setup and turbulence model. Furthermore, the results lead to suggest that large eddy simulations are superior to unsteady Reynolds-averaged Navier-Stokes simulations when instantaneous stresses are applied for the blood damage prediction.

Zinc remediation of aqueous streams is of special concern due to its highly toxic and persistent nature. Conventional treatment technologies for the removal of zinc are not economical and further generate huge quantity of toxic chemical sludge. Biosorption is emerging as a potential alternative to the existing conventional technologies for the removal of metal ions from aqueous solutions. Mechanisms involved in the biosorption process include chemisorption, complexation, adsorption-complexation on surface and pores, ion exchange, microprecipitation, heavy metal hydroxide condensation onto the bio surface, and surface adsorption. Biosorption largely depends on parameters such as pH, the initial metal ion concentration, biomass concentration, presence of various competitive metal ions in solution, and to a limited extent on temperature. Biosorption using biomass such as agricultural wastes, industrial residues, municipal solid waste, biosolids, food processing waste, aquatic plants, animal wastes, etc., is regarded as a cost-effective technique for the treatment of high volume and low concentration complex wastewaters containing zinc metal. Very few reviews are available where readers can get an overview of the sorption capacities of agro based biomasses used for zinc remediation together with the traditional remediation methods. The purpose of this review article is to provide the scattered available information on various aspects of utilization of the agro based biomasses for zinc metal ions removal. An extensive table summarizes the sorption capacities of various adsorbents. These biosorbents can be modified using various methods for better efficiency and multiple reuses to enhance their applicability at industrial scale. We have incorporated most of the valuable available literature on zinc removal from waste water using agro based biomasses in this review.

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