Abstract: The use of a multi-functional, chromophore containing, polymerizable compound for producing an optical element having non-linear optical properties (an NLO element) wherein the multi-functional chromophore is a compound capable of being polymerized into a cross-linked network and of being poled under the influence of an electric field whilst being polymerized into the cross-linked network, the compound having the generalized formula(D) (C) (A) (F)D, C, A and F representing covalently linked moieties where C represents at least one conjugated system of .pi.-bonds,A and D represent at least one respectively .pi.-electron acceptor and .pi.-electron donor groups linked at opposite ends of the conjugated system, and are preferably conjugated with the conjugated system of .pi.-bonds (C) and where more than one moiety A, C or D is present they may be the same or different,F represents at least two polymerizable functional groups, which may be the same or different, attached to the .pi.

Abstract: Amphiphilic compounds and oligomers and polymers derived therefrom suitable for Langmuir Blodgett deposition wherein the compounds have a polyamide backbone and hydrophobic groups pendant therefrom which pendant groups preferably contain chromophore groups. The compounds can be used to form non-centrosymmetric bilayers and are useful for forming various non-linear optical elements.

Abstract: Metal values are extracted from aqueous solutions containing halide or pseudohalide anion using 1,1'-substituted 2,2'-biimidazole or bibenzimidazole compounds. Useful for the solvent extraction of zinc and copper from chloride leach solutions.

Abstract: Metal values are extracted from aqueous solutions containing halide or pseudohalide anion using 1,1'-substituted 2,2'-biimidazole or bibenzimidazole compounds. Useful for the solvent extraction of zinc and copper from chloride leach solutions.