often an important process in industry and chemical analysis. Liquid-membrane transport in which the extraction and stripping operations are combined in a single process reduces the solvent inventory requirement, and also allows the use of expensive and highly selective extractions, which otherwise would be uneconomic in solvent extractants. For these reasons, liquid-membrane transport has attr...

We show how zinc may easily be quantified in serum by first using an optimum concentration of guanidine hydrochloride to cause release of zinc from proteins, followed by complexation of released metals with cyanide. The cyanide complex of zinc is preferentially demasked with chloral hydrate, followed by a colorimetric reaction between zinc and 4-(2-pyridylazo)resorcinol. This is a sensitive wat...

a new kinetic spectrophotometic method for the determination of trace amount chromium (iii) in teareal samples has been described based on it s the catalytic effect on the oxidations of 1 - ( 2 –pyridylazo ) - 2 - naphthol, (pan), by potassium bromated in sulfuric acid. the reaction is followedspec- trophotometrically by measuring the decrease in the absorbance at 469 nm. under the optimumcondi...