A simple and sensitive method is described for the pre-concentration by cloud point extraction followed by atomic absorption spectrometric determination of copper ion in real samples. At a solution pH of 5.5, 5, 5-diphenylimidazolidine-2, 4-dione (phenytoin) (DFID) and TritonX-114 were used as hydrophobic ligand and non-ionic surfactant. The adopted concentrations for DFID, Triton X-114 and HNO...

This paper introduces an implicit scheme for a   continuous representation of nonexpansive mappings on a closed convex subset of a Hilbert space with respect to a   sequence of invariant means defined on an appropriate space of bounded, continuous real valued functions of the semigroup.   The main result is to    prove the strong convergence of the proposed implicit scheme to the unique solutio...