2-phosphonobutane-1,2,4-tricarboxylic acid is(pbtc) a member of phosphonate family, and used as corrosion and scale inhibitor in cooling water systems. phosphonocarboxylates as a member of organophosphorus compounds have c-p and p-o bonds in their structures. pbtc is mainly used as carbonate scale inhibitor (caco3), sulphate scale inhibitor (caso4), corrosion inhibitor of low alloyed steel, eff...

Two new integrable nonlocal Davey–Stewartson equations are introduced. These equations provide two-spatial dimensional analogues of the integrable, nonlocal nonlinear Schrö-dinger equation introduced in Ablowitz and Musslimani (2013 Phys. Rev. Lett. 110 064105). Furthermore, like the latter equation, they also possess a PT symmetry and, as it is well known, this symmetry is important for the ...

We prove that the Davey-Stewartson approximation (which degenerates into a cubic Schrödinger equation in 1D) furnishes a good approximation for the exact solution of a wide class of quadratic hyperbolic systems. This approximation remains valid for large times of logarithmic order. We also consider the general case where the polarized component of the mean field needs not to be well-prepared. T...