University of North Florida
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Stuart Chalk, Ph.D.
Department of Chemistry
University of North Florida
Phone: 1-904-620-1938
Fax: 1-904-620-3535
Website: @unf

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Classification: Alloy -> bronze

Citations 3

"An Online Solid Phase Extraction System Using Polyurethane Foam For The Spectrophotometric Determination Of Nickel In Silicates And Alloys"
Anal. Chim. Acta 1999 Volume 378, Issue 1-3 Pages 287-292
Sérgio Luis Costa Ferreira, Djane Santiago de Jesus, Ricardo Jorgensen Cassella, Antonio Celso Spinola Costa, Marcelo Souza de Carvalho and Ricardo Erthal Santelli

Abstract: The present paper describes the use of a solid phase extraction system using a polyurethane foam (PUF) minicolumn, in order to separate nickel from interferences due to other elements and determine it by flow injection analysis with spectrophotometric detection. Separation is based on the retention of thiocyanate complexes of interferent ions in the PUF minicolumn. Nickel does not form complex with thiocyanate and pass through the minicolumn and then it can be determined by using 4-(2-pyridylazo)-resorcinol (PAR) as chromogenic reagent. So, parameters such as thiocyanate concentration and pH effects on the separation efficiency, sorption capacity of the polyurethane foam minicolumn, influence of the flow rates, PAR concentration, pH effect on the chromogenic reaction, minicolumn regeneration, analytical features and others were investigated. The results demonstrated that nickel (at concentration of 0.5 mg/ml) can be quantitatively separated from iron and copper (200 mg/ml), zinc and cobalt (100 mg/ml) by using a minicolumn containing 0.125 g of polyurethane foam. Nickel can be determined with great selectivity and sensitivity and the procedure was applied for nickel determination in brass, bronze, steel and rock certified reference materials. The results showed satisfactory accuracy and precision. The limit of detection was 77 ng/ml and the RSD was 2.63%. A dynamic range from 0.25 up to 5.00 µg/ml and a sample throughput of 24 samples per hour were achieved.
Nickel Spectrophotometry Solid phase extraction Column Preconcentration Reference material Optimization

"Rapid Determination Of Copper In Various Copper Base Alloys By Flow Injection Analysis"
Bunseki Kagaku 1980 Volume 29, Issue 10 Pages T73-T78

Abstract: A flow injection method is described for the spectrophotometric determination of copper in various types of copper-base alloys. The system utilizes either the light absorption of aquacopper(II) ion at 805 nm or the light absorption of colored complex of copper(II) with EDTA (730 nm). Simple dissolution of alloys in nitric acid in the presence of tartaric acid suffices for sample preparation. The procedures have been applied to standard samples of copper-base alloys including several types of brasses, beryllium copper, deoxidized copper, German silver and aluminum bronze. The results obtained agree very satisfactorily with the certified values for these alloys. The precision is better than 0.5 % for the aquacopper(II) ion method. The sampling rate is 1 7 samples per hour.
Copper Spectrophotometry Method comparison Reference material

"Fluorimetric Determination Of Beryllium With 3-hydroxy-2-naphthoic Acid By Flow Injection Analysis After Preconcentration On A Silica Gel Micro-column"
Collect. Czech. Chem. Commun. 1989 Volume 54, Issue 7 Pages 1777-1784
Kuban, V.;Havel, J.;Patockova, B.

Abstract: Sample solution of Be (200 ppb) in 0.1 M ammonium acetate (I) at pH 7.1 is passed through a column (4 cm x 2 mm) of silica gel (0.05 to 0.1 or 0.2 mm) pre-washed with 0.1 M I. After washing the column with water, Be is eluted with 0.1 M HCl, the eluate is mixed with 50 µM-3-hydroxy-2-naphthoic acid in 0.1 M I - 0.1 M NH3, and the fluorescence of the resulting solution is measured at 455 nm (excitation at 355 nm). The limit of determination is 10 ppb. The method was applied in the determination of Be (1 to 6%) in bronze and foundry dust. Bronze samples were dissolved in HCl - H2O2, with evaporation to dryness and dissolution in dilute HCl; dusts were dry-ashed at 550°C and the residue was dissolved in dilute HNO3.
Beryllium Sample preparation Fluorescence Silica gel Column PPB Preconcentration