Publications by authors named "Ridvan N Fernandes"

This paper describes a new technique for the determination of captopril in pharmaceutical formulations, implemented by employing multicommuted flow analysis. The analytical procedure was based on the reaction between hypochlorite and captopril. The remaining hypochlorite oxidized luminol that generated electromagnetic radiation detected using a homemade luminometer.

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A flow system for the simultaneous determination of ammonium and phosphate in river water at the mug ml(-1) level employing a low expensive LED-based photometer is described. The manifold of the flow system comprised four analytical pathways containg a set of three-way solenoid valves and an automatic injector commutator. The signal measurements of both analytes were carried out using two LED-based photometers attached to the flow cells.

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A multicommutated flow system for simultaneous determination of iron and chromium in steel alloys by photometry is described. The flow network consisted of an automatic injector and four solenoid valves assembled to form two independent analytical pathways, each one comprising reaction coils and a flow cell. The light source (LED) and detector (photodiode) were attached to the flow cells to form a compact unit.

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