  We study the fluctuations of net-charge, net-pion, net-kaon and net-proton
using $D$-measure and $\nu_{dyn}$ variables in heavy-ion jet interaction
generator (HIJING), ultra-relativistic quantum molecular dynamics (UrQMD), and
hadron resonance gas (HRG) model at different collision energies \sqsn. It has
been observed that, the values of $D$ strongly dependent on $\Delta \eta$ in
HIJING and UrQMD models and independent in HRG model. The diffusion
coefficients ($\sigma$) of identified particles are estimated at various \sqsn.
It is observed that, the $\sigma$ values are independent of collision energies
but emphasizes the particle species dependence of diffusion coefficient in the
QGP medium. This study provides a realistic baseline for comparison with the
experimental data.
