University of North Florida
Browse the Citations

Contact Info

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

View Stuart Chalk's profile on LinkedIn

Commercial product

Classification: Commercial product -> glass

Citations 7

"A Collaborative Study For The Determination Of Mercury In Glass Packaging By Cold Vapor Atomic Absorption Spectrometry - A Report Of ICG/TC2, Chemical Durability And Analysis"
Glass Technol. 2001 Volume 42, Issue 1 Pages 24-29
E.Guadagnino, P.Sundberg and H.J.Heinrich

Abstract: Within the frame of the requirements set out by the Packaging Directive 62/94, this paper recommends a method for the determination of mercury by cold vapor atomic absorption spectrometry (CVAAS). The study consisted of two ports: (i) a recovery study.; (ii) a collaborative intercomparison carried out on an experimental glass incorporating Hg in traces. During the recovery study the decomposition solution of a Hg free container glass was spiked with known amounts of Hg which were fully recovered by CVAAS. No significant interferences were found from other hydride forming elements. An intercomparison among ten laboratories carried out on a glass incorporating Hg traces showed an acceptable reproducibility (CV 8.9%) at a mean concentration level of 1.10 mg/kg. The determination limit was estimated as 0.1 mg Hg/kg of glass. Inductively coupled plasma optical emission spectrometry (ICP-OES), used as an alternative to CVAAS, showed a limit of determination of 7.2 mg/kg, which was considered quite inadequate, with respect to the average mean value of Hg possibly present in packaging.
Mercury Spectrophotometry Interferences Method comparison

"Micellar Systems In Flow Injection For The Spectrophotometric Determination Of Neodymium In Glasses"
Analyst 1989 Volume 114, Issue 7 Pages 849-851
José Luis Pérez Pavón, Bernardo Moreno Cordero, Jesús Hernández Méndez and Jorge Cerdá Miralles

Abstract: Glass (~0.25 g) was dissolved as previously described (Anal. Abstr., 1988, 50, 8B222), the pH of the solution was adjusted to 2.7 and NaNO3 was added to a final concentration. of 0.4M. After dilution to 25 ml, a 143 µL portion of solution was injected into the carrier stream (2.2 mL min-1), viz, of aqueous 1.6 mM 1-(2-pyridylazo)-2-naphthol - Triton X-100 (150:1), buffered at pH 9.2 with 0.04 M HBO2 - NaBO2. A 50-cm reaction coil was used, and the absorbance was measured at 560 nm. Interference from heavy metals was removed by extracting their diethyldithiocarbamates into CHCl3 - ethyl acetate (1:1). The detection limit was 27 ppb and the calibration graph was rectilinear from 56 to 80 µM-Nd. Results agreed with those obtained by conventional and derivative spectrophotometriy.
Neodymium Sample preparation Spectrophotometry Buffer Interferences Method comparison PPB Triton X Micelle Surfactant

"Determination Of Cobalt In Two Glasses By Atomic Absorption Spectrometry After Flow Injection Ion-exchange Preconcentration"
Analyst 1991 Volume 116, Issue 11 Pages 1141-1144
M. C. Valdés-Hevia y Temprano, J. Pérez Parajón, M. E. Díaz García and A. Sanz-Medel

Abstract: Ground glass (0.5 g) was digested with concentrated HNO3 - concentrated HCl04 - HF (details given) and the digest was treated with HCl, boric acid, NaOH and sodium citrate. After dilution with 0.1 M ammonium acetate - HCl buffer solution of pH 2.7 (buffer A), a 1 mL portion of the solution was injected into a carrier stream (0.5 mL min-1) of buffer A and passed through a reaction coil (3 ml). The mixture was merged with a second carrier stream (2.5 mL min-1) of 1 M NH3 - NH4Cl buffer solution of pH 8.5 and passed sequentially through a reaction coil (5 m) and a minicolumn (10 cm x 3 mm) loaded with Chelex-100. After 5 to 6 min, 200 µL of 5 M HNO3 was injected into the system to elute the Co directly into the nebulizer of the spectrometer. A schematic diagram of the flow manifold is given; operating conditions are tabulated. The calibration graph was rectilinear for 1.2 µg mL-1 of Co; the detection limit was 20 ng mL-1. For 0.5 µg mL-1 of Co, the coefficient of variation (n = 10) was 1.5%. The detection limit was 4-fold better than that obtained by direct aspiration without pre-concentration.
Cobalt Sample preparation Ion exchange Spectrophotometry Buffer Column Nebulizer Preconcentration Column Chelex

"Analysis Of Solid Samples By ICP-mass Spectrometry"
Fresenius J. Anal. Chem. 1992 Volume 342, Issue 12 Pages 917-923
Uwe Voellkopf, M. Paul and E. R. Denoyer

Abstract: ICP-mass spectrometry is typically used as a technique for very rapid multielement analysis at trace and ultratrace levels of solutions by continuous sample aspiration and nebulization. However, ICP-MS is well suited to be used as a detector for other sample introduction devices. For the analysis of solid samples laser sampling and electrothermal vaporization accessories may be used as sample introduction devices for ICP-MS. Laser sampling permits the analysis of many different types of solid materials. For solid sampling ETV-ICP-MS analysis it is of advantage to reduce the sample to a fine powder prior to analysis. For automated analysis powders may be introduced as slurries into the graphite furnace by means of a slurry sampling device. Since appropriate certified solid reference materials are not always available for calibration, or since they are not certified for all analyte elements of interest, the analyzes discussed in this contribution were performed semi-quantitatively. The instrument response function was established using reference materials which were similar in their composition to the samples. The results of semi-quantitative bulk analyzes of glass (NIST 612) and geological material (USGS GXR-3) by laser sampling ICP-MS are in good agreement with the certified values. The concentrations. of the analytes determined in the glass sample were in the range of 10 µg/g to 80 µg/g. The lowest analyte concentration in the geological sample was 0.4 µg/g (Eu) and the highest was approximately 186 mg/g (Fe). The precision achieved was in the order of 5% to 15%. Laser sampling ICP-MS is not only suitable to bulk analysis but also to analyzes where spatial information is required. As an example for such an application the determination of Pb in a wine bottle cork stopper is discussed. The slurry sampling technique was used for the semi-quantitative analysis of NIST coal reference samples by electrothermal vaporization ICP-MS. The accuracy achieved with this approach was within a factor of ±2 of the reference values.
Iron Europium Lead Mass spectrometry Reference material Slurry Ultratrace

"A New Concept For The Quasi Non-destructive Microsampling Of Historical Glasses"
Fresenius J. Anal. Chem. 1997 Volume 358, Issue 6 Pages 694-698
G. Schulze, I. Horn, H. Bronk

Abstract: A glass object was sampled by filing with a diamond-coated Cr file. For the determination of Si, the file was sonicated for 20 min in 5 mL 6% Na2CO3/K2CO3 (1:1) to remove the sample material, and was also washed with water. The slurry and washings were combined and evaporated to dryness, and then fused at 1000°C for 20 min. For other determinations, the file was immersed in 0.4 mL HF or HF/HClO4 (3:1), then rinsed with water. The combined solution and washings were evaporated to dryness and the residue was reconstituted prior to analysis. Digestion of the residue with Cl/H2O was used prior to the determination of Au. Si and P were determined by FIA with photometric detection (based on the molybdenum blue reaction). Other elements were determined by ion chromatography or GFAAS (details given).
Gold Silicon Phosphorus Spectrophotometry Sample preparation Sample preparation

"Water-soluble Azo-reagents Of High Sensitivity And Their Applications"
Huaxue Shiji 1987 Volume 9, Issue 5 Pages 282-287
Nigita Hiroko

Abstract: A review is presented of the use of high-sensitivity reagents comprising pyridylazo- and azo-derivatives, in many of which sulfo-groups are introduced to increase solubility in water, for the determination of Ca, Mg, Cu, Fe, Zn, Ag, Ba or Co in drinking water, serum, glass, steel or nickel salts by flow injection AAS or spectrophotometric methods. (15 references).
Calcium Magnesium Copper Cobalt Iron Zinc Silver Barium Spectrophotometry Spectrophotometry Review

"FIA-AAS Determination Of Potassium, Sodium, Calcium, Magnesium And Iron In Fluorescent Screen Glass"
Lihua Jianyan, Huaxue Fence 1994 Volume 30, Issue 3 Pages 144-147
Zhang Jiankang, Zhou Yali, Luo Xiyun and Jin Ping

Abstract: Two manifolds for flow injection AAS are described (diagrams given) and experimental parameters were selected for the cited determination (details given). Dried sample was placed in a Pt crucible, treated with water, HF and H2SO4 and the mixture was evaporated to dryness. The residue was dissolved in dilute HCl and diluted with water before analysis. The absorbance of K, Na, Ca, Mg and Fe were measured at 766.5, 5890.6, 422.7, 282.2 and 248.3 nm, respectively. Recoveries ranged from 93-110%. The calibration graphs were linear from 1-10, 0-3.2, 10^-26, 0.04-1.2 and 0.5-15.5 µg/ml for K, Na, Ca, Mg and Fe, respectively, and their corresponding detection limits were 0.1, 0.03, 0.25, 0.04 and 0.05 µg/ml. Interference was studied by injecting sample solution into a carrier stream containing interferents. Results (tabulated) are discussed
Potassium Sodium Calcium Magnesium Iron Spectrophotometry Interferences