Birla Institute of Technology and Science

About: Birla Institute of Technology and Science is a education organization based out in Pilāni, Rajasthan, India. It is known for research contribution in the topics: Computer science & Population. The organization has 8897 authors who have published 13947 publications receiving 170008 citations.

Wormholes in R-2-gravity within the f (R, T) formalism

Abstract: We propose, as a novelty in the literature, the modeling of wormholes within a particular case of f(R, T) gravity, namely $$f(R,T)=R+\alpha R^{2}+\lambda T$$ , with R and T being the Ricci scalar and trace of the energy-momentum tensor, respectively, while $$\alpha $$ and $$\lambda $$ are constants. Although such a functional form application can be found in the literature, those concern compact astrophysical objects, such that no wormhole analysis has been done so far. The quadratic geometric and linear material corrections of this theory render the matter content of the wormhole remarkably able to obey the energy conditions.

Epoxidation of karanja (Pongamia glabra) oil catalysed by acidic ion exchange resin

Abstract: Karanja oil with an iodine value of 89 g/100 g was epoxidised in situ with aqueous hydrogen peroxide and acetic acid in the presence of Amberlite IR-120 acidic ion exchange resin as catalyst. The effect of the operating variables on the oxirane oxygen content, as well as on the oxirane ring stability and the iodine value of the epoxidised karanja oil, were determined. The variables studied were stirring speed, hydrogen peroxide-to-ethylenic unsaturation molar ratio, acetic acid-to-ethylenic unsaturation molar ratio, temperature, and catalyst loading. The effects of these parameters on the conversion to the epoxidised oil were studied and the optimum conditions for the maximum oxirane content were established. The proposed kinetic model takes into consideration the two side reactions, namely, epoxy ring opening involving the formation of hydroxy acetate and hydroxyl groups, and the reaction between the peroxyacid and the epoxy group. The kinetic and adsorption constants of the rate equations were estimated by the best fit using Marquardt's algorithm. Good agreement between experimental and predicted data validates the proposed kinetic model. From the estimated kinetic constants, the apparent activation energy for the epoxidation reaction was found to be 11 kcal/mol.