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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Commercial product

Classification: Commercial product -> paint

Citations 4

"Determination Of Hexavalent Chromium In Industrial Hygiene Samples Using Ultrasonic Extraction And Flow Injection Analysis"
Analyst 1997 Volume 122, Issue 11 Pages 1307-1312
Jin Wang, Kevin Ashley, Eugene R. Kennedy and Charles Neumeister

Abstract: A simple, fast, and sensitive method was developed for the determination of hexavalent chromium (Cr(VI)) in workplace samples. Ultrasonic extraction in alkaline solutions with 0.05 M (NH4)2SO4-0.05 M NH3 provided good extraction efficiency of Cr(VI) from the sample and allowed the retention of Cr(VI) on an ion-exchange resin (95%). The Cr(VI) in the sample solution was then separated as an anion from trivalent chromium [Cr(III)] and other cations by elution from the anion-exchange resin with 0.5 M (NH4)2SO4 in 0.1 M NH3 (pH 8) buffer solution. The eluate was then acidified with hydrochloric acid and complexed with 1,5-diphenylcarbazide reagent prior to flow injection analysis. By analyzing samples with and without oxidation of Cr(III) to Cr(VI) using Ce(IV), the method can measure Cr(VI) and total Cr. For optimizing the separation and determination procedure, preliminary trials conducted with two certified reference materials (CRMs 013-050 and NIST 1633a) and three spiked samples (ammonia buffer solution, cellulose ester filters and acid washed sand) indicated that the recovery of Cr(VI) was quantitative (> 90%) with this method. The limit of detection for FIA-UV/VIS determination of the Cr-diphenylcarbazone complex was in the sub-nanogram range (0.11 ng). The technique was also applied successfully to a workplace coal fly ash sample that was collected from a power plant and paint chips that were collected from a heating gas pipe and a university building. The principal advantages of this method are its simplicity, sensitivity, speed and potential portability for field analysis.
Chromium(VI) Chromium(III) Sample preparation Spectrophotometry Reference material Speciation

"Sample Analysis By Online Isotope-dilution Inductively Coupled Plasma Mass Spectrometry"
J. Anal. At. Spectrom. 1989 Volume 4, Issue 8 Pages 761-766
Alexandra Lásztity, Miklós Viczián, Xioaru Wang and Ramon M. Barnes

Abstract: A system for online isotope-dilution ICP-MS was developed by coupling commercial flow injection instruments with an ICP-MS instrument. The performance of the system was investigated by determination of Pb in various standard reference materials (including soil, sediment, paint, blood and food), with dilution with 206Pb or radiogenic Pb isotope standards. Both steady-state merging and multiple injections were employed, the former being preferred, the precision was 1%.
Lead Mass spectrometry Mass spectrometry Reference material

"Vapor Generation-FTIR Direct Determination Of Acetone And Isopropanol In Nitrocellulose Paints"
Quim. Anal. 1998 Volume 17, Issue 1 Pages 21-28
E. López-Anreus, S. Garrigues and M. de la Guardia

Abstract: Paint (1 g) was diluted with 4 mL CCl4 then centrifuged at 4000 rpm for 4 min in order to separate the binder from the solvent. A 1 l portion of supernatant was injected into a Pyrex vessel, of 2.5 mL internal volume, and heated at 80°C. The volatilized solvents were swept in a stream of N2 (350 ml/min) into a Magna 750 Nicolet FTIR spectrometer equipped with an ultramini long-path cell with a total volume of 100 mL and an optical path length of 3.2 m. Vapour phase FTIR spectra were recorded between 2000 and 500 cm-1 as a function of time at a nominal resolution of 8 cm-1 with accumulation of two scans for each spectrum. Acetone and isopropanol were determined by measurement of peak height or peak area of the flow injection recording obtained from the absorbances of the transient signals in the ranges 1743-1737 and 956-950 cm-1, respectively. Limits of detection based upon measurement of peak height and peak area were 3.9 and 1.6 and 0.8 and 0.5 g for acetone and isopropanol, respectively. For 120 g of either solvent the RSD were 0.8-0.9% (n = 5). Recoveries were 95.5-104.8% and sample throughput was 50/h.
Acetone 2-Propanol Spectrophotometry Volatile generation Gas phase detection