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: Metal -> aluminum

Citations 6

"Determination Of Uranium And Thorium In Aluminum With Flow Injection And Laser-ablation Inductively Coupled Plasma Mass Spectrometry"
J. Anal. At. Spectrom. 1991 Volume 6, Issue 8 Pages 609-614
Peter van de Weijer, Peter J. M. G. Vullings, Wilhelmina L. M. Baeten and Wim J. M. de Laat

Abstract: Two sample introduction techniques, viz, flow injection (FI) and laser-ablation (LA), were investigated for use in the determination of sub ng g-1 levels of U and Th in Al used for wiring in integrated circuits. With the FI method, the achievement of sub ng g-1 detection limits was hampered by the presence of 'spikes'; although these spikes were present when the LA method was used, as low as 0.2 ng g-1 of U and Th could be determined by rejecting all measurements containing spikes.
Thorium-232 Uranium Mass spectrometry Laser

"Carrier Precipitation And Flotation Of Traces Of Phosphate In Highly Concentrated Sodium Chloride Solutions"
Anal. Sci. 1994 Volume 10, Issue 3 Pages 389-392

Abstract: Al (0.5 g) was dissolved in 25 mL of hot 4 M HNO3, diluted to 100 mL with water and portions (2 ml) were mixed with 200 mL of aqueous 30% NaCl. Aqueous 15 M NH3 solution was added dropwise to form a flocculent precipitate, 6 mL of 1 mg/ml sodium oleate and 2 mL of 1 mg/ml sodium dodecylbenzenesulfonate (both in aqueous 70% ethanol) were added and the mixture was transferred to a glass flotation cell (illustrated). N2 was bubbled (2 ml/cm2. min) through the sintered glass disk for 2 min to float the precipitates as a foam. After suction-removal of the mother liquor and aqueous washing, the foam was destroyed with 5 mL of ethanol, the precipitates were dissolved 1 M HNO3 and the filtrate was diluted to 20 mL with 1 M HNO3. Portions (200 µL) were injected into a carrier stream (0.8 ml/min) of 1 M HNO3 which merged with a stream (0.8 ml/min) of 4 mM ammonium molybdate in 0.2 M HNO3/0.5% ascorbic acid in 10% glycerol (1:1) and passed through a reaction coil (10 m x 0.5 mm i.d.; 80°C) to a detector for determination of the phosphomolybdenum-blue complex at 660 nm. The calibration graph was linear for up to 20 µg of phosphate and the detection limit was 8 ng/g. Si and As(V) did not interfere.
Phosphate Spectrophotometry Sample preparation Heated reaction Interferences Precipitation

"Determination Of Beryllium With Salicylidene - Ethylenediamine By Flow Injection Fluorimetry"
Bunseki Kagaku 1992 Volume 41, Issue 1 Pages 11-16

Abstract: Sample solution (65 µL, containing 65 ng of Be) is injected into a carrier stream of water that merges with a stream of 0.6 M ethylenediamine - 0.25 mM salicylaldehyde (pH 8.5); the mixture is passed through a 1-m mixing coil and a 12 µL flow cell for measurement of the fluorescence at 435 nm (excitation at 335 nm). The calibration graph is rectilinear for 0.7 ppb to 1.0 ppm of Be and the detection limit is 0.2 ppb. The coefficient of variation (n = 10) at 5 ppb of Be was 0.7%. The sampling rate is 30 h-1. Up to a 1000-fold concentration. of Al with respect to Be can be masked with triethanolamine. Results agreed well with those obtained by ICP-AES. Fluorimetric determination of Be by flow injection analysis was investigated based on the formation of Be Schiff base complex by the reaction of ethylenediamine with salicylaldehyde. The calibration curve was linear over the range of 0.7 ppb to 1 ppm of Be. The detection limit was 0.2 ppb (S/N = 3). The relative standard deviation for 5 ppb of Be was 0.68% (n = 10). The sampling rate was 30 samples/h. Al(III) up to 1000-fold concentration. of Be was masked with triethanolamine. The proposed method was applied to the determination of 0.5 ppm Be in Al metals. In this case, the Be was pre-concentrated by the extraction of the Be complex formed with acetylacetone. The method was also successfully applied to Be-Cu alloys.
Beryllium Fluorescence Sample preparation Method comparison Preconcentration Extraction

"Determination Of Beryllium In Aluminum Metals With 2-hydroxy-1-naphthaldehyde And Methylamine By Flow Injection Fluorimetry"
Bunseki Kagaku 1995 Volume 44, Issue 8 Pages 633-639
Watanabe, K.;Ikai, T.;Itagaki, M.

Abstract: The sample solution (0.4 ml), containing fluoride and hexasodium triethylenetetramine-NNN'N''N'''N'''-hexaacetate, is injected into a carrier stream of water (1.6 ml/min) that then merges with streams (each 0.2 ml/min) of 2.5 mM 2-hydroxy-1-naphthaldehyde in 1,4-dioxane and aqueous 1.5 M methylamine, and after passage through a 0.5 m reaction coil the fluorescence intensity of the merged streams (pH 11.0) is measured at 435 nm in a 27 µL flow cell (excitation at 365 nm). Concentrations of Be >1.8 ppm in aluminum can be determined.
Beryllium Fluorescence pH

"Fluorescence Spectrophotometric Determination Of Trace Manganese(II) By An Optical Fibre Kinetic Method - Flow Injection Analysis With A Manganese/thiamine/sodium Periodate System"
Fenxi Huaxue 1995 Volume 23, Issue 3 Pages 299-301
Wang, J.F.;Zhang, Z.J.

Abstract: Standard Mn(II) solution was mixed with 8 mL 0.1 M nitrilotriacetic acid and water was added to 25 mL. A portion of the solution was injected into the flow system and mixed with streams (2.5 ml/min) of 0.15 mM thiamine and 0.4 mM NaIO4 in a reaction tube (500 cm x 2 mm i.d.) before entering an optical fiber luminescence detection flow cell (3 cm x 2 mm i.d.) for detection with use of a Shimadzu RF-540 fluorescence spectrophotometer. The calibration graph was linear for 8.2 ng/ml to 1 µg/ml of Mn and the detection limit was 0.4 ng/ml. The RSD (n = 11) was 0.8%. There was no interference. The method was applied to the direct assay of Al and Al alloys. Sampling frequency was 45 runs/h.
Manganese(II) Fluorescence Interferences Optical fiber Kinetic

"Flow Injection Spectrophotometric Determination Of A Micro Amount Of Titanium Using O-nitrophenylfluorone And Hexadecyltrimethylammonium Bromide"
Fenxi Shiyanshi 1994 Volume 13, Issue 2 Pages 41-43
Shen, H.X.;Liu, Y.G.;Wang, X.J.;Liu, L.Z.

Abstract: Sample (80 µL) was injected into the flow injection analyzer. and carried in a stream of water at 4.2 ml/min to react with streams (1.3 ml/min) of 0.3 mM o-nitrophenylfluorone, 6 mM cetyltrimethylammonium bromide and 0.15 M H2SO4 in a reaction tube (100 cm long, 1 mm i.d.) before detection at 542 nm. The linearity range was 0.1 µg/g of Ti. Interferences due to Zr(VI), Sn(IV), Mo(VI), Nb and Ta could be overcome by masking and pre-treatment. The sampling rate was 100 runs/h. The method was used to determine Ti in alloy steels and pure Al.
Titanium Spectrophotometry Interferences