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
Email: schalk@unf.edu
Website: @unf

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Alloy

Classification: Alloy -> copper nickel

Citations 4

"Flow Injection Extraction Spectrophotometric Determination Of Nickel Using Bis(acetylacetone)ethylenediimine"
Anal. Chim. Acta 2000 Volume 408, Issue 1-2 Pages 123-127
N. Chimpalee, D. Chimpalee, P. Keawpasert and D. Thorburn Burns

Abstract: Nickel was determined by flow injection spectrophotometry at 370 nm after extraction of nickel(II) bis(acetylacetone)ethylenediiminate chelate into chloroform. The carrier stream was deionized water and the reagent streams were phosphate buffer (pH 7.0) and 1.5% (w/v) bis(acetylacetone)ethylenediimine solutions. The reaction stream was heated to 60degC and then cooled to room temperature prior to extraction into chloroform. The sampling rate was 18 h-1. The calibration graph was linear up to 25 µg mL-1 nickel, based on injection volumes of 250 µL. The relative standard deviation (n=10) was 0.98% for 20 µg mL-1 nickel. The system has been applied to the determination of nickel in nickel-copper alloys and in synthetic electroplating solutions.
Nickel Spectrophotometry Extraction Complexation Heated reaction

"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

"Flow Injection Extraction-spectrophotometric Determination Of Manganese(VII) With Benzyltributylammonium Cations"
Anal. Chim. Acta 1992 Volume 270, Issue 1 Pages 213-215
D. Thorburn Burns*, S. A. Barakat, M. Harriott and M. S. El-Shahawi

Abstract: Steel (500 to 2000 µg) was dissolved in H2SO4 - H3PO4 (35 ml), followed by oxidation with HNO3 (2 ml) and boiling to expel nitrous acid fumes; any carbides remaining were evaporated. To the cooled solution water (50 ml) and concentrated HNO3 (5 ml) were added. The solution was boiled for 2 min and 0.5% KIO3 (10 ml) was added followed by boiling for a further 4 min. The solution was then cooled and transferred to a 100 mL volumetric flask and made up to volume with water. The peak height was measured using the flow injection system. Sample was injected into a carrier stream of phosphate buffer (pH 6) which was merged with aqueous NH4F solution (0.70 mL min-1), mixed with aqueous 0.10% benzyltributylammonium chloride solution (0.67 mL min-1) in a coil (25 cm x 0.5 mm). The aqueous phase was mixed with CHCl3 and passed through an extraction coil (150 cm x 0.5 mm) followed by a phase separator. The organic phase was used for the spectrophotometric determination of the Mn(VII) complex at 548 nm. The calibration graph was rectilinear from 0 to 25 µg mL-1 and the detection limit was 0.91 g mL-1 of Mn, (for 250 µL injections). The method was also applied to the determination of Mn in copper - nickel alloy. A flow injection manifold has been developed for the spectrophotometric determination of manganese(VII) at 548 nm after extraction into chloroform of the ion-associated, benzyltributylammonium permanganate. The carrier stream was a pH 6 buffer containing 10%(w/v) ammonium fluoride and the reagent stream was 0.10%(w/v) benzyltributylammonium chloride. The injection rate was 20 h-1. The calibration graph is linear up to 25 µg mL-1 and the detection limit (3 x baseline noise) is 0.91 µg mL-1 Mn(VII), based on 250 µL injection volumes The system has been applied to the determination of manganese in steels and a cupro-nickel alloy.
Manganese(7+) Sample preparation Spectrophotometry Sample preparation Organic phase detection Ion pair extraction Phase separator

"Flow Injection Extraction-spectrophotometric Determination Of Permanganate With The Triphenylsulfonium Cation"
Fresenius J. Anal. Chem. 1992 Volume 344, Issue 3 Pages 131-132
D. Thorburn Burns Contact Information, S. A. Barakat, M. S. El-Shahawi and M. Harriott

Abstract: Sample solution was injected into a carrier stream (0.7 mL min-1) of buffer solution (pH 6) containing 10% NH4F which merged sequentially with a stream (0.69 mL min-1) of aqueous 0.1% triphenylsulfonium chloride and a stream (0.7 mL min-1) of CHCl3. The mixture passed through an extraction coil (150 cm x 0.5 mm) and a phase separator and the absorbance of the organic phase was measured at 548 nm. The calibration graph was rectilinear up to 40 µg mL-1 of MnO4-; the detection limit was 1.1 µg mL-1. Sample throughput was 20 h-1. The method was used in the analysis of steel and alloys. Permanganate can be determined spectrophotometrically at 548 nm after flow injection extraction into chloroform of the ion-associated triphenylsulfonium permanganate. The carrier stream was a pH 6 buffer containing 10% (w/v) ammonium fluoride and the reagent stream was 0.10% (w/v) triphenylsulfonium chloride. The injection rate was 20 h-1. The calibration graph is linear up to 40 µg mL-1 and the detection limit is 1.10 µg mL-1 Mn(VII), based on injection volumes of 250 µL. The system has been applied to the determination of manganese in steels and a cupro-nickel alloy.
Permanganate Spectrophotometry Sample preparation Extraction Phase separator Organic phase detection