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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NIST 1571

Classification: Reference Material -> NIST -> 1571 -> Orchard leaves

Citations 6

"Temporal And Organ-specific Variability Of Selenium In Marine Organisms From The Eastern Coast Of India"
Adv. Environ. Res. 2001 Volume 5, Issue 2 Pages 167-174
Amit Chatterjee, Badal Bhattacharya and Rajdulal Das

Abstract: Temporal and organ-specific variations of selenium concentration in selected coastal organisms (seagrass, bivalves and fish) were investigated in different biotopes of the deltaic Sundarbans, in the eastern coastal region of India. The bivalves and fish were obtained from local fishermen and were destined for human consumption. The samples were digested with HNO3-H2O2 and selenium was extracted from the aqueous solution with triisooctylamine and stripped with dilute hydrochloric acid. The concentration of selenium was measured by hydride generation-atomic absorption spectrometry. The results obtained were verified using inductively coupled plasma-mass spectrometric and fluorometric methods. The mean selenium concentration found in the various species ranged from 0.05 to 3.94 µg g-1 (dry wt.). It was observed that bivalves accumulated more selenium compared to fish and seagrass. The sequence of selenium levels found was, bivalves > fish > seagrass. In seagrass, the selenium concentration was higher in the roots (0.21±0.03 µg g-1; dry wt.) than the stems (0.17±0.02 µg g-1; dry wt.) and the leaves (0.11±0.01 µg g-1; dry wt.). But, in bivalves, the maximum concentration of selenium was found in the gill (3.94±0.11 µg g-1; dry wt.). The results of the analysis of variance indicated that significant differences in Se concentration were evident between seasons and organs in these species. The variations in uptake of selenium may be due to different metabolic requirements for selenium among the three species, variations in food and differences in interspecies retention and elimination mechanisms.
Selenium Spectrophotometry Method comparison

"A Flow Injection/hydride Generation System For The Determination Of Arsenic By Inductively-coupled Plasma Atomic Emission Spectrometry"
Anal. Chim. Acta 1984 Volume 161, Issue 1 Pages 275-283
R. R. Liversage and J. C. Van Loon, J. C. De Andrade

Abstract: After optimizing the concentration. of HCl and NaI in the test solution, the concentration. of NaBH4, sample and reductant volume and flow rate, Ar carrier-gas flow rate and r.f. power, As (10 to 1000 ppb) was determined in NBS orchard leaves, coal fly ash and river sediment and NRCC MESS-1 and BCSS-1 standard reference materials with good accuracy and precision by using an ARL 34000 Quantometer. The coefficient of variation (n = 10) at the 100-ppb level of As was 7.2%, and the detection limit was 1.4 ng for a 0.17 mL sample volume The calibration graph was rectilinear for 0.01 to 1 ppm of As. Cobalt, Ni, Ag, Au, Bi, Te and Sn interfered. About 200 injections h-1 were possible.
Arsenic Spectrophotometry Interferences Reference material

"Determination Of Cadmium By Suction-flow Liquid - Liquid Extraction Combined With Inductively Coupled Plasma Atomic-emission Spectrometry"
Anal. Chim. Acta 1985 Volume 174, Issue 1 Pages 183-189
Takahiro Kumamaru, Yoko Nitta, Fumio Nakata and Hiroshi Matsuo, Masahiko Ikeda

Abstract: A flow-manifold system is proposed that permits specific online suction-flow liquid extraction of Cd as its diethyldithiocarbamate from a discrete aqueous sample into CCl4 (I). The organic extract is fed into the nebulizer of the ICP spectrometer by a peristaltic pump, to achieve a 250-fold increase in sensitivity compared with direct aspiration of the aqueous solution The sampling frequency is 20 h-1 and the consumption of I and of 5% (w/v) Na diethyldithiocarbamate solution is 0.6 mL min-1. The calibration graph is rectilinear up to 300 ppb of Cd, the detection limit is 0.4 ppb, the coefficient of variation (n = 10) at the 50-ppb level is 1.5%, and only Mn(II), Co(II) and Ni interfere significantly. Such interference can be decreased or eliminated by the addition of citrate to the buffer solution Interference by large amounts of alkali and alkaline-earth metals and most anions can be avoided by extraction. The proposed method was applied to the determination of Cd in NBS SRM 1571 orchard leaves, NIES (Japan) CRM No. 1 pepperbush and CRM No. 6 mussel to give results in good agreement with the certified values.
Cadmium Spectrophotometry Sample preparation Interferences Nebulizer Reference material Solvent extraction

"Hydride-generation Atomic Absorption Spectrometry Coupled With Flow Injection Analysis"
Anal. Chem. 1985 Volume 57, Issue 7 Pages 1382-1385
Manabu Yamamoto, Makoto Yasuda, and Yuroku Yamamoto

Abstract: Flow injection analysis was combined with the gas-segmentation method described by Skeggs (Am. J. Clin. Pathol., 1957, 28, 311) for the determination of As, Sb, Bi, Se and Te. On synthetic samples the coefficient of variation were between 0.5 and 0.8% (n = 10) with detection limits between 0.04 and 0.3 ng. The results on NBS steel, wheat and rice flour, orchard leaves and coal fly ash were close to certified values and the differential determination of As and Sb in thermal water was possible. Tolerance limits for diverse ions are listed.
Arsenic Antimony Bismuth Selenium Tellurium Spectrophotometry Reference material Segmented flow

"Determination Of Arsenic And Selenium By Hydride Generation Atomic Absorption Spectrometry Using A Gas-liquid Separator And A Dehydration Trap"
Microchem. J. 1996 Volume 53, Issue 1 Pages 18-25
Hisatake Narasaki and Jun-Yan Cao

Abstract: Biological material (0.25 g) was allowed to stand overnight in 3 mL concentrated HNO3, 0.5 mL concentrated H2SO4 and 1 mL 60% HClO4 were added and the mixture was digested under low heat until the fumes of HClO4 subsided. The digests, including siliceous residues, were transferred to a Pt dish with water and evaporated to 2 mL. The residues were dissolved with 5 mL 46% HF, 1 mL 9 M H2SO4 was added and the solution was concentrated to 2 mL. The pH was adjusted to 3.5 with 1 M NH3 and applied to a SPE column (35 cm x 10 mm i.d.) packed with 10 cm Chelex 100 chelating ion-exchange resin and the column was washed with 2 x 10 mL water. For the analysis of As; the column effluents were diluted to 100 mL with water and a 10 mL portion was mixed with 5 mL 6 M HCl. Portions of both acid solutions were introduced into the flow injection hydride generation system (schematic shown) and mixed with a stream of 2% sodium tetrahydroborate(III) solution in a Pyrex mixing coil (16 cm x 2 mm i.d.). The hydride generated was collected in a gas-liquid separator, dehydrated in a dehydration trap and swept into an electrically heated furnace with a carrier stream of N2 (2.5 l/min) by manipulating electromagnetic relays and timers (operating details given). The atomized As and Se species were detected at 193.7 and 196 nm, respectively, by AAS. The detection limits were 0.6 and 1 ng/ml, respectively. Tolerance levels to 10 foreign ions are listed. The method was applied to the analysis of five NIST Standard Reference materials (listed). Results agreed well with certified values.
Arsenic Selenium Spectrophotometry Reference material Chelex

"Hydride-generation Flow Injection Using Graphite Furnace Detection - Emphasis On Determination Of Tin"
Spectrochim. Acta B 1992 Volume 47, Issue 5 Pages 701-709
Zhang Li, Susan McIntosh, Glen R. Carnrick and Walter Slavin*

Abstract: Hydride-forming analytes were separated from large volume of matrix by trapping the hydrides on a Pd-coated L'vov platform at low temperature before analysis by AAS. The Pd-treated stabilized-temp. platform furnace was used for in situ trapping and atomization of the analyte, and was at least 80% efficient for As, Bi, Ge, Sb, Se, Sn and Te. The method was tested by determining Sn in steel, river sediment, orchard leaves and bovine liver standard reference materials. The detection limit for Sn was 7 ng l-1, and the coefficient of variation was 31.5% at the 1.0 ng level. Other hydride-forming elements did not interfere.
Arsenic Bismuth Germanium Antimony Selenium Tellurium Tin Spectrophotometry Interferences Volatile generation Reference material Volatile generation