Flow-injection determination of phosphate species in detergents with a calciumion-selective electrode

A calcium ion-selective electrode is applied for the determination of ligands which complex calcium ions. The response of the electrode is measured when ligand solutions are injected into a buffered carrier stream containing calcium. Injections of EDTA, citrate, tripolyphosphate and pyrophosphate provide peaks with heights dependent on both the ligand and calcium concentrations. Ligand concentrations down to. 2 × 10^?5 M can be detected. Tripolyphosphate in detergents is easily determined. Use of the electrode has advantages over spectrophotometric methods for phosphates in flow systems.     

An approach to the analysis of crosslinked epoxy systems

Summary The most widely use epoxy resins are the diglycidylethers of bisphenol A which in both the uncured and curd states posses functional groups that are theoretically amenable to cleavage using the vigorous conditions possible with acid or alkaline fusion chromatography.The cleavage of the simple oligomeric epoxy resins has been investigated together with their crosslinked products with diprimary amines of increasing molecular weight, several polyamines and dimer fatty polyamides. The results are discussed with regard to other polymer systems incorporating bisphenol A.Dedicated to Professor Leslie S. Ettre on the occasion of his 70th birthday.