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 -> water -> snow

Citations 14

"Flow Injection Chemiluminescent Determination Of Trace Amounts Of Hydrogen Peroxide In Snow Water Using KIO4-K2CO3 System"
Anal. Chim. Acta 1998 Volume 371, Issue 2-3 Pages 171-176
Jin-Ming Lin*, Hajime Arakawa and Masaaki Yamada

Abstract: In the absence of a specific luminescent reagent, the chemiluminescence (CL) from the reaction of periodate with H2O2 in an aqueous alkaline solution was observed The CL intensity was enhanced by the addition of K carbonate to the alkaline solution The ratio of the signal-to-noise (S/N) is proportional to the concentration. of H2O2 up to 1 x 10^-5 M. The detection limit with the flow injection method is 5 x 10^-9 M H2O2 (S/N=3). The relative standard deviation (RSD) for 4 x 10^-8 M H2O2 is 2.8% (n=14). Sample throughput is ~100/h. The selectivity of this method is very high, and most of the transition metal ions have no effect on the determination This method was applied to the determination of trace amounts of H2O2.
Hydrogen peroxide Chemiluminescence Indirect Interferences

"Continuous-flow Determination Of Chloride In The Nonlinear Response Region With A Tubular Chloride Ion-selective Electrode"
Talanta 1987 Volume 34, Issue 11 Pages 921-926
Hirokazu Hara* and Yoshiki WakizakaSatoshi Okazaki

Abstract: The tubular electrode is constructed from copper pipe (2 cm x 0.28 cm) plated internally with silver, which is then electro-oxidized in 0.1 M KCl to form a AgCl layer. This electrode is used in conjunction with an Orion double-junction reference electrode containing 1 M NaNO3 in 30% methanol solution as outer filling solution The electrode is incorporated into a microcomputer-aided flow system in which sample or standard solution is mixed with colloidal AgCl solution to remove Br- and I- before the sample is passed through the tubular electrode. The concentration. is interpolated with use of the spline function in the range 0.1 to 10 mg L-1 and the corresponding coefficient of variation were 10 to 2% (n = 5). The detection limit is ~0.1 mg l-1. Results of analysis of rain and snow containing >0.75 mg L-1 of Cl-1 agreed within 10% of those of ion chromatography (n = 12).
Chloride Electrode Potentiometry Computer Method comparison

"Ultratrace Analysis Of Antarctic Snow And Ice Samples Using High Resolution Inductively Coupled Plasma Mass Spectrometry"
J. Anal. At. Spectrom. 1998 Volume 13, Issue 5 Pages 463-468
Ashley T. Townsend and Ross Edwards

Abstract: High resolution ICP-MS was used to determine the concentrations of Al, Sc, V, Mn, Fe, Co, Pb and Bi in snow and ice from Antarctica. To overcome some potentially problematic spectral interferences, measurements were acquired in both low and medium resolution modes. Small sample volumes were analyzed using a microconcentric nebulizer. After rigorous instrument cleaning and sample preparation, detection levels in the low and sub-pg g-1 range (0.3-48 pg g-1) were found for all elements. Concentration. values were determined for a continental snow, sea ice snow and a representative ice core. Concentration. ranges for all snow samples (n = 25) were (in pg g-1): Al (30-2000), V (2-16), Mn (2-30) and Fe (30-1500), while Sc and Co were typically below detection or blank limits. The ice core sample had Al, Mn, Fe and Pb concentrations of 90, 7, 110 and 1 pg g-1, respectively, while Sc, V, Co and Bi could not be quantified (below detection or blank limits). The reliability of the analytical method for Fe was confirmed by flow injection analysis with spectrophotometric detection.
Aluminum Scandium Vanadium Manganese Iron Cobalt Lead Bismuth Mass spectrometry Interferences Method comparison

"Fluorimetric Flow Injection Determination Of Aqueous Peroxides At Nanomolar Level Using Membrane Reactors"
Anal. Chem. 1986 Volume 58, Issue 7 Pages 1521-1524
Hoon Hwang and Purnendu K. Dasgupta

Abstract: The simultaneous determination of H2O2 and methyl hydroperoxide was based on their reaction with 4-hydroxyphenyl acetate(I) and peroxidase to give the fluorescent dimer of the ester. The enzyme was mixed with the merged analyte - I stream in the pressurized porous PTFE membrane reactor and the flow stream then passed through a second membrane reactor where infused NH3 raised the pH to 10. The stream then passed into a 30 µL flow cell for fluorimetric detection at 412 nm (excitation at 329 nm). The detection limit was 0.1 µg L-1 of H2O2 and the sample throughput was 50 h-1. The sample could be optionally routed through a reactor containing granular MnO2 before injection into the analytical system for the differential determination of H2O2 and organic peroxides. The method was used to determine H2O2 in snow.
Hydrogen peroxide Methylhydroperoxide Fluorescence Enzyme Reactor Teflon membrane

"Amperometric Flow Injection Technique For Determination Of Hydrogen Peroxide And Sulfur(IV) In Atmospheric Liquid Water"
Fresenius J. Anal. Chem. 1989 Volume 335, Issue 8 Pages 919-923
I. G. R. Gutz and D. Klockow

Abstract: Hydrogen peroxide and S(IV) were determined in atmospheric water (200 µL) by flow injection analysis with electrochemical oxidation in a specially designed micro-cell (described and illustrated) with an alkaline carrier stream for H2O2 and an acidic carrier stream for S. Differential measurements before and after addition of catalase or sulfite oxidase were taken using an amperometric detector. Sample throughput was 30 h-1. The electroactive species could be determined from 20 nM (detection limit) to mM levels. The method was applied to rain, snow, fog and cryosampled atmospheric water vapor. Sulfur(IV) present as hydroxymethanesulfonate or in the form of other carbonyl adducts was determined after alkaline decomposition to liberate SO32-.
Hydrogen peroxide Sulfur Amperometry Enzyme

"Flow Injection Spectrophotometric Determination Of Calcium In Rain And Snow With Chlorophosphonazo III"
Fresenius J. Anal. Chem. 1990 Volume 338, Issue 6 Pages 707-709
Michio Zenki, Kikuko Ohmuro and Kyoji Tôei

Abstract: A two-fold manifold (diagram given) is used for the determination of Ca in rain and snow based on the complex formation with chlorphosphonazo III in the presence of 0.01 M oxalate (pH 2.8). Barium, Sr and rare-earth metals interfered. Under optimum conditions, the calibration curve was rectilinear up to 1.2 ppm Ca and the detection limit was 0.01 ppm for 120 µL of sample. The coefficient of variation for 0.4 and 1.0 ppm Ca were 0.354 and 0.352%, respectively. Results agreed well with those obtained by AAS.
Calcium Spectrophotometry pH Interferences Method comparison Detection limit Optimization

"Continuous Measurement Of Sulfate Ion In Environmental Water Samples By FIA"
Bunseki Kagaku 1990 Volume 39, Issue 9 Pages T129-T133
Korenaga, T.;Okada, K.;Takahashi, T.;Moriwake, T.

Abstract: The determination of SO42- in water samples, e.g., rain and snow, was achieved by using a FIA sensing device equipped with a double plungent micropump; an aqueous 80% ethanol solution containing a Ba - sulfonazo III complex and EDTA was used as color reagent for SO42-. Results agreed well with those obtained by the official titration method (r = 0.99). The coefficient of variation was 0.5% and the detection limit was 0.02 mg L-1 of SO42-. The method was applied to waste water.
Sulfate Spectrophotometry Method comparison Detection limit

"Flow Injection Analysis Of Hydrogen Peroxide, Sulfite, Formaldehyde And Hydroxymethanesulfonic Acid In Precipitation Samples"
Int. J. Environ. Anal. Chem. 1987 Volume 31, Issue 2-4 Pages 263-279
Keuken, M.P.;Bakker, F.P.;Lingerak, W.A.;Slanina, J.

Abstract: A flow injection apparatus was constructed (illustrated schematically), which permits such analyzes. Determination of H2O2 involved amperometric oxidation with Pt working and auxiliary electrodes at 250 mV (Ag - AgCl reference electrode). The detection limit was 5 µg L-1 and the response was rectilinear up to 5 mg l-1. Selective and sensitive spectrophotometric detection of SO32-, formaldehyde and hydroxymethanesulfonic acid is described. For SO32- the reaction involved di-4-pyridyl disulfide; indirect procedures for the organic analytes are described. The limit of detection was 50 µg L-1 and response was rectilinear up to 5 mg l-1.
Hydrogen peroxide Sulfite Formaldehyde Hydroxymethanesulfonic acid Amperometry Spectrophotometry Electrode Indirect

"Non-sea-salt Contribution Of Some Chemical Species To The Snow Composition At Terra Nova Bay (Antarctica)"
Int. J. Environ. Anal. Chem. 1996 Volume 63, Issue 3 Pages 207-223
Piccardi, G.;Casella, F.;Udisti, R.

Abstract: Snow was analyzed for H2O2, anions and cations by methods described previously. These were ion chromatography for anions and cations (Udisti et al., 1994, 349, 289) and flow injection fluorimetry using p-hydroxyphenylacetic acid and peroxidase for H2O2 (Ibid., 1994, 55, 219). Results for two series of samples collected in the Terra Nova Bay are presented and discussed.
Anions Cations Hydrogen peroxide Fluorescence HPLC

"Multiparametric Approach For Chemical Dating Of Snow Layers From Antarctica"
Int. J. Environ. Anal. Chem. 1996 Volume 63, Issue 3 Pages 225-244
R. Udisti

Abstract: The method is based on the determination of H2O2 (by flow injection fluorimetry, cf. Lazrus et al., Anal. Chem., 1985, 57, 917), methanesulfonic acid (by ion chromatography on a Dionex A55A column using 1.8-30 mM Na2B4O7) and non-sea salt sulfate. The latter was determined by measurement of sulfate and chloride by ion chromatography on a Dionex A54A column using a mobile phase containing 1.2 mM NaHCO3 and 1.3 mM Na2CO3 and measurement of Na+ by ion chromatography on a Dionex CS 10 column using 20 mM HCl/0.5 mM diaminopropionic acid as mobile phase. These compounds demonstrate summer maxima and winter minima values. The method involved searching for the maximum value and normalization of the concentration depth profile of each compound.
Hydrogen peroxide Fluorescence HPIC

"Flow Injection Analysis. Spectrophotometric Determination Of Sulfate Ions In Atmospheric Deposits"
J. Anal. Chem. 1987 Volume 42, Issue 9 Pages 1631-1635
Eremina, I.D.;Shpigun, L.K.;Zolotov, Y.A.

Abstract: A Tecator flow injection analysis-Star 5020/003 analyzer. with a spectrophotometric detector is used for determining 0.2 to 20 mg L-1 of SO42- in rain and melted snow. A 200 µL sample is injected into a carrier stream of pure water (2 mL min-1) and, after passing through a column (15 cm x 4 mm) of KU-2 cation exchanger (H+ form) to remove interfering metal ions, the sample zone is merged with a stream of standard solution (1.4 mL min-1) containing 10 mg L-1 of SO42-. Thereafter the stream is mixed with a stream of reagent (0.75 mL min-1) containing 25 µM-BaCl2 and 31 µM-3-(2-carboxyphenylazo)-6-(2-sulfophenylazo)chromotropic acid(I); 30-cm mixing coils are used. The decrease in absorbance of the Ba(II) - I complex at 620 nm is related to the concentration. of SO42- in the sample. Sample throughout is 40 h-1; the coefficient of variation are <2% (n = 8). The manifold must be washed with 50 mM Na2EDTA periodically to remove pptd. BaSO4.
Sulfate Spectrophotometry Interferences Tecator

"Flow Injection Analysis. Spectrophotometric Determination Of Hydrogen Peroxide In Atmospheric Precipitation With Use Of Peroxidase"
J. Anal. Chem. 1989 Volume 44, Issue 2 Pages 341-345
Eremina, I.D.;Shpigun, L.K.;Zolotov, Y.A.

Abstract: A system based on a Tecator FIAstar-5020 analyzer. is used for determining 50 nM-H2O2 in fresh snow. Melted snow (200 µL) is injected into a carrier stream of water (0.8 mL min-1), which is merged successively with a stream of 10 mM acetate buffer of pH 4.6 containing 20 µg mL-1 of 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonate) (I) as chromogenic reagent (flow rate 0.6 mL min-1) and a stream of the same buffer containing 20 µg mL-1 of horse-radish peroxidase (0.6 mL min-1). After passing the solution through a 30-cm mixing coil, the transient absorbance of the oxidation product of I is measured at 412 nm. The sample throughput is 80 h-1. Copper, Pb, Mn(II), Co, Ni and 100 µg L-1 of Fe(III) can be tolerated. The coefficient of variation are 5% (n = 10) for 0.1 to 10 µM-H2O2.
Hydrogen peroxide Spectrophotometry Buffer Tecator Chromogenic reagent

"Flow Injection Analysis. Spectrophotometric Determination Of Fluoride In Atmospheric Precipitations"
J. Anal. Chem. 1990 Volume 45, Issue 3 Pages 462-467
Eremina, I.D.;Shpigun, L.K.;Dedkova, V.P.;Zolotov, Y.A.;Savvin, S.B.

Abstract: The method is based on the catalytic effect of F- on the reaction of Zr(IV) with 2,7-bis(2-hydroxy-3-sulfo-5-chlorophenylazo)-1,8-dihydroxynaphthalene-3,6-disulfonic acid (sulfochlorophenol S; I). Rain-water or melted snow (200 µL) was injected into a carrier stream of water (2 mL min-1) which was merged successively with reagent streams (0.6 mL min-1) of (i) 0.1 mM I in 23 mM HCl - 77 mM glycine - 77 mM NaCl buffer (pH 2.8) and (ii) 0.1 mM ZrOCl2 in 0.1 M HCl. The mixture was passed through a reaction coil and the absorbance was measured at 640 nm. A computer-controlled Tecator FIA star-5020 analyzer. was used with a throughput of 90 samples h-1. From 0.02 to 2 mg L-1 of F- could be determined. Calcium and SO42- ions interfered at >20 and >40 mg l-1, respectively. The coefficient of variation for 0.3 to 0.4 mg L-1 of F- were 3%.
Fluoride Spectrophotometry Catalysis Automation Interferences Tecator

"Determination Of Trace Molybdenum In Water Samples By Electrothermal Atomic Absorption Spectrometry After Preconcentration With Miniaturized Coprecipitation"
Bull. Chem. Soc. Jpn. 1999 Volume 72, Issue 1 Pages 43-46
Tokuo Shimizu, Hirobumi Ito, Hiroshi Kawaguchi and Yoshio Shijo

Abstract: Miniaturized coprecipitation with hydrous manganese(IV) oxide was studied for the pre-concentration of sub µg dm-;3 levels of molybdenum in water samples. Manganese(IV) oxide was produced by a reaction of permanganate ion with ethanol in the presence of 0.1 mol dm-;3 hydrochloric acid. A nanogram amount of molybdenum in a 10 mL sample was quantitatively coprecipitated. The amount of manganese required was 0.1-0.40 mg for a 10 mL sample. The precipitate was collected on a 10 µm membrane filter, and then dissolved in 50 mm3 of 5.6 mol dm-;3 nitric acid and 75 mm3 of 1% hydrogen peroxide. An 80-fold pre-concentration factor was obtained by this procedure. The molybdenum concentration was determined by electrothermal atomic absorption spectrometry using a pyrolytic graphite coated cuvette. The detection limit (3s) was found to be 8.9 ng dm-;3. The proposed method was successfully applied to river water and snow samples.
Molybdenum Spectrophotometry Coprecipitation