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: Environmental -> sediment -> marine

Citations 7

"Sequential Injection Analysis System For Determination Of Mercury By Cold Vapor Atomic Absorption Spectroscopy"
Anal. Chim. Acta 1997 Volume 355, Issue 2-3 Pages 203-210
F. M. Bauzá de Mirabóa, A. Ch. Thomasa, E. Rubíb, R. Fortezaa and V. Cerdàa,*

Abstract: A sequential injection system is proposed for the determination of mercury by cold vapor atomic absortion spectrometry. Both the sample and the reagent are sequentially aspirated using a Crison automatic Compact Titrator and impelled into a gas-liquid separation cell. Once there, a N2 flow sweeps the reduced mercury into a measuring cell of an atomic absortion spectrometer. The system proposed allows the detection of mercury in addition to data acquisition and treatment in an automatic way. The linear calibration range ranges between 2 and 50 ug L-1 Hg, the detection limit being 0.34 ug l-1. The relative standard deviation of the method is 0.95% when 0.8 mL of 25 ugl-1 Hg is aspirated. The sampling rate allowed by this method is 30 injections per hour. The proposed method has been applied to different certified fish and marine sediment samples for which satisfactory results were obtained.
Mercury Spectrophotometry Sequential injection Volatile generation

"Determination Of Cadmium By Flow Injection Isotope-dilution Inductively Coupled Plasma Mass Spectrometry With Vapor-generation Sample Introduction"
J. Anal. At. Spectrom. 1997 Volume 12, Issue 5 Pages 579-584

Abstract: The sample (0.1 ml) is injected into a carrier stream of 2% thiourea/0.0002% Co solution in 0.1 M HCl (4.8 ml/min), which then merges with a stream of 4% NaBH4 solution in 0.1 M NaOH (2.4 ml/min) for passage to a gas-liquid separator that consists essentially of a vessel (diagram presented), containing 120 glass beads (5 mm diameter), from which the Cd-containing vapor is carried to the ICP by a stream of Ar. Interference from MoO+ and ZrO+ is thereby alleviated. Sample-preparation procedures are described for sediments, urine and water, in which 111Cd is added as the tracer; the result is calculated by use of the equation proposed previously (Ibid., 1996, 11, 353). The detection limit is 26 pg/ml of Cd. Recoveries of 5 ng/ml of Cd added to standard refence waters were quantitative, and the results for standard reference freeze-dried urine and marine sediments agreed well with the certified values.
Cadmium Mass spectrometry Mass spectrometry Detection limit Interferences Isotope ratio Reference material Glass beads Volatile generation Volatile generation

"Sequential Determination Of Tin, Arsenic, Bismuth And Antimony In Marine Sediment Material By Inductively Coupled Plasma Atomic Emission Spectrometry Using A Small Concentric Hydride Generator And L-cysteine As Prereductant"
Fresenius J. Anal. Chem. 1998 Volume 361, Issue 2 Pages 155-157
Y.-L. Feng A, H.-Y. Chen A, H.-W. Chen A, Li-Ching Tian

Abstract: A hydride generation system using a small concentric hydride generator combined with inductively coupled plasma atomic emission spectrometry (ICP-AES) was established to determine tin, arsenic, bismuth and antimony in a marine sediment material with L-cysteine as a pre-reductant. Influences of concentrations of three kinds of acids (HCl, HNO3 and HClO4), L-cysteine, and sodium tetrahydroborate(III) as well as sodium hydroxide were investigated. The interferences from transition ions were found to be insignificant for determination of the four elements in presence of L-cysteine. Under optimized conditions the detection limits were 0.6 ng/mL for arsenic(III), 0.8 ng/mL for antimony(III), 1.7 ng/mL for tin(IV), and 1.2 ng/mL for bismuth(III). The method was applied to determine the four elements in standard marine sediment materials and the results were in agreement with certified values.
Tin Arsenic Bismuth Antimony Mass spectrometry Phase separator Volatile generation Apparatus

"Flow Injection Online Preconcentration And Flame AAS Determination Of Copper, Cadmium And Lead In Marine Sediment Samples"
Anal. Lett. 1997 Volume 30, Issue 5 Pages 1037-1050
S. Kartikeyan; B. Vijayalekshmy; S. Chandramouleeswaran; T. P. Rao; C. S. P. Iyer

Abstract: Marine sediment (0.25 g) was mixed with 5 mL of 48% HF, 30 mL of 70% HNO3 and 2-5 drops of 98% H2SO4 and the mixture was digested (details given). Sample and ammoniacal dithizonate solutions were pumped simultaneously and mixed online. Preconcentration was performed on a C18 column over 1 min and Cu, Cd and Pb were eluted with acidified methanol and injected directly into the nebulizer for atomization in an air-acetylene flame. The calibration graph was linear from 1-40, 0.6-8 and 3-40 ppb, with detection limits of 1.2, 0.6 and 3 ppb Cu, Cd, and Pb, respectively. RSD were
Copper Cadmium Lead Sample preparation Spectrophotometry C18 Preconcentration

"Comparison Of Acid Mixtures In High-pressure Microwave Digestion Methods For The Determination Of The Total Mercury In Sediments By Cold Vapor Atomic Absorption Spectrometry"
Anal. Sci. 1996 Volume 12, Issue 3 Pages 471-476
C. Y. ZHOU, M. K. WONG, L. L. KOH and Y. C. WEE

Abstract: Four acid mixtures, viz. HNO3/H2SO4, HNO3/HClO4, HNO3/HCl and HNO3/HCl/HF, were evaluated as solvents for the high-pressure microwave digestion of environmental sediments for analysis of total Hg by cold vapor AAS. Sediments were dried at 105°C for 4 h and a 300 mg portion of each was digested with 14 mL of each acid mixture (acid ratios given) in an MDS-2000 Microwave System (CEM Corp., Mathews, NC, USA) operated at 630 W power, 150 psi pressure and 200°C for 30 min. After digestion, the samples were cooled until the pressure in the vessels was reduced to 50 psi, filtered and the filtrate was diluted to 50 mL with water. A 10 mL portion of the diluted filtrate was mixed with 0.2 mL 5% KMnO4 solution and a 500 µL portion of the mixture was injected into a Perkin-Elmer FIA System interfaced with a Perkin-Elmer 4100ZL atomic absorption spectrometer (instrumental details given) for measurement of Hg absorbance at 253.6 nm. Best results were obtained with the HCl/HNO3/HF mixed acid solvent. The method was successfully applied to the analysis of three sediment reference materials, viz. NIST SRM 1645 River Sediment, NIES CRM No. 2 Pond Sediment and NRCC BCSS-1 Marine Sediment with recoveries of 92-108%.
Mercury Sample preparation Spectrophotometry Reference material Optimization

"Semi-automatic Hydride Generation And Atomic Absorption Determination Of Bismuth With Insitu Concentration In A Graphite Furnace"
Bull. Korean Chem. Soc. 1991 Volume 12, Issue 3 Pages 290-295
Yong-Keun Lee*, Dong Soo Lee, Byung Mok Yoon, and Hoon Hwang

Abstract: A semi-automatic method for the determination of dissolved bismuth at parts per trillion levels is described. The method involves bismuthine generation, in situ collection of bismuthine in a graphite furnace, and atomic absorption detection. In order to facilitate semi-automation of bismuthine generation and separation from aqueous solution, Gore-tex microporous PTEE membrane is used. The absolute detection limit, taken as three times the standard deviation of the instrument noise is 2 pg. The precisions are 3.1% for 100 pg and 1.9% for 1 ng of bismuth, respectively. As many as 90 measurements can be made in an hour.
Bismuth Spectrophotometry Interferences Volatile generation Volatile generation

"Flow Injection Analysis Of Iron In Marine Sediments"
Haiyang Yu Huzhao 1987 Volume 18, Issue 2 Pages 156-161
Yuan, Youxian

Abstract: A flow injection analysis using the Fe(II)-bathophenanthroline-Triton X-100 system was developed and applied to the determination of Fe in marine sediments. The method is simple and selective. One hundred determinations can be run in an hour, and 50 mL of sample volume is required for each determination The linear range for calibration curve and detection limit are 0.5-4.0 and 0.02 ppm Fe, respectively. The coefficient of variation for 3.0 ppm Fe solution is 2.0%.
Iron Spectrophotometry