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Ravinder, R.

Publications and source records attributed to Ravinder, R..

Density–stiffness scaling in minerals upon disordering: Irradiation vs. vitrification

When subjected to irradiation or vitrification, minerals become disordered at the atomic scale, which, in turn, affect their density and stiffness. However, the nature of the relationship between structural disorder, density, and stiffness remains poorly understood. In this work, based on molecular dynamics simulations, we investigate the effect of irradiation- and vitrification-induced disordering in a series of silicate minerals. We show that irradiation- and vitrification-induced disordering yield comparable, yet not fully equivalent variations in density and stiffness. Interestingly, we report the existence of a power law density–stiffness scaling exhibiting a scaling exponent that is similar to that observed in porous assembled cellular materials.

36 MATERIALS SCIENCE↗

On-three time scale analysis

In the present consideration of a three-timescale system, a block diagonalization employing three-stage linear transformations is used to decouple the original system into slow, fast, and faster subsystems. A numerical algorithm is given to solve the resulting Ricatti-type equations, and the technique is verified for the case of a ninth-order example. The technique yields substantial computational requirment reductions, since it involves subsystems that are of a lower order than the original system.

Naidu, D. S.↗