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Atomic Absorption Spectrometer
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Shang-da Huang – One of the best experts on this subject based on the ideXlab platform.
Direct and simultaneous determination of arsenic, manganese, cobalt and nickel in urine with a multielement graphite furnace Atomic Absorption Spectrometer.Talanta, 2004Co-Authors: Man-ching Hsiang, Yu-hsiang Sung, Shang-da HuangAbstract:
Abstract A simple method was developed for the direct and simultaneous determination of arsenic (As), manganese (Mn), cobalt (Co), and nickel (Ni) in urine by a multi-element graphite furnace Atomic Absorption Spectrometer (Perkin–Elmer SIMAA 6000) equipped with the transversely heated graphite atomizer and longitudinal Zeeman-effect background correction. Pd was used as the chemical modifier along with either the internal furnace gas or a internal furnace gas containing hydrogen and a double stage pyrolysis process. A standard reference material (SRM) of Seronorm™ Trace Elements in urine was used to confirm the accuracy of the method. The optimum conditions for the analysis of urine samples are pyrolysis at 1350 °C (using 5% H2 v/v in Ar as the inter furnace gas during the first pyrolysis stage and pure Ar during the second pyrolysis stage) and atomization at 2100 °C. The use of Ar and matrix-free standards resulted in concentrations for all the analytes within 85% (As) to 110% (Ni) of the certified values. The recovery for As was improved when mixture of 5% H2 and 95% Ar (v/v) internal furnace gas was applied during the first step of a two-stage pyrolysis at 1350 °C, and the found values of the analytes were within 91–110% of the certified value. The recoveries for real urine samples were in the range 88–95% for these four elements. The detection limits were 0.78 μg l−1 for As, 0.054 μg l−1 for Mn, 0.22 μg l−1 for Co, and 0.35 μg l−1 for Ni. The upper limits of the linear calibration curve are 60 μg l−1 (As); 12 μg l−1 (Mn); 12 μg l−1 (Co) and 25 μg l−1 (Ni), respectively. The relative standard deviations (R.S.D.s) for the analysis of SRM were 2% or less. The R.S.D.s of a real urine sample are 1.6% (As), 6.3% (Mn), 7.0% (Ni) and 8.0% (Co), respectively.
Simultaneous determination of manganese, iron and cobalt in copper with a multi-element graphite furnace Atomic Absorption SpectrometerSpectrochimica Acta Part B: Atomic Spectroscopy, 2003Co-Authors: Chun-hao Chiu, Yu-hsiang Sung, Shang-da HuangAbstract:
Abstract A simple method was developed for the determination of trace metals (Mn, Fe and Co) in copper simultaneously using a multi-element graphite furnace Atomic Absorption Spectrometer (Perkin-Elmer SIMAA6000) equipped with a transversely heated graphite atomizer. Copper was dissolved in nitric acid before analysis using a microwave digestion system. Pd(NO 3 ) 2 with the special gas (5% H 2 in Ar) was used as the chemical modifier. The accuracy of the method was confirmed by the analysis of certified reference copper (CRM#075). The interferences were removed effectively, so that a calibration curve method based on simple aqueous standards could be used. The analyzed values were in the range of 96.6% (Mn) to 113% (Co) of the certified values. The relative standard deviations for the simultaneous determination of Mn (6.5 μg/l), Fe(18 μg/l) and Co(5 μg/l) in solution from copper are 2.4–3.5% and the detection limits were 0.17 μg/g for Mn, 0.50 μg/g for Fe and 0.30 μg/g for Co.
Direct determination of cadmium and copper in seawater using a transversely heated graphite furnace Atomic Absorption Spectrometer with Zeeman-effect background corrector.Talanta, 2000Co-Authors: Mei-shu Chan, Shang-da HuangAbstract:
Abstract Methods for the direct determination of copper and cadmium in seawater were described using a graphite furnace Atomic Absorption Spectrometer (GFAAS) equipped with a transversely heated graphite atomizer (THGA) and a longitudinal Zeeman effect background corrector. Ammonium nitrate was used as the chemical modifier to determine copper. The mixture of di-ammonium hydrogen phosphate and ammonium nitrate was used as the chemical modifier to determine cadmium. The matrix interference was removed completely so that a simple calibration curve method could be applied. This work is the first one with the capability of determining cadmium in unpolluted seawater directly with GFAAS using calibration curve based on simple aqueous standards. The accuracy of the methods was confirmed by analysis of three kinds of certified reference saline waters. The detection limits (LODs), with injection of a 20-μl aliquot of seawater sample, were 0.06 μg l −1 for copper and 0.005 μg l −1 for cadmium.
Bradley T. Jones – One of the best experts on this subject based on the ideXlab platform.
Evaluation of a continuum source tungsten coil Atomic Absorption Spectrometer: a study of Zn behaviorJournal of the Brazilian Chemical Society, 2005Co-Authors: Joaquim A. Nóbrega, Jennifer A. Rust, Clifton P. Calloway, Bradley T. JonesAbstract:
The performance of a tungsten coil atomizer Atomic Absorption Spectrometer with a D2 lamp continuum source, a Czerny-Turner monochromator, and a charge coupled device detector was evaluated for the determination of Zn. The main attractive characteristics of the instrument are its simplicity and the relative low cost of the atomizer. In spite of a poor limit of detection (40 µg L-1, 3 blank standard deviation/slope), Zn was accurately determined in one water and one urine certified reference standards. The recovery in water was 106% and in urine the obtained result is in the acceptable certified range.
Analytical characteristics of a continuum-source tungsten coil Atomic Absorption Spectrometer.Analytical Sciences, 2005Co-Authors: Jennifer A. Rust, Joaquim A. Nóbrega, Clifton P. Calloway, Bradley T. JonesAbstract:
A continuum-source tungsten coil electrothermal Atomic Absorption Spectrometer has been assembled, evaluated, and employed in four different applications. The instrument consists of a xenon arc lamp light source, a tungsten coil atomizer, a Czerny-Turner high resolution monochromator, and a linear photodiode array detector. This instrument provides simultaneous multi-element analyses across a 4 nm spectral window with a resolution of 0.024 nm. Such a device might be useful in many different types of analyses. To demonstrate this broad appeal, four very different applications have been evaluated. First of all, the temperature of the gas phase was measured during the atomization cycle of the tungsten coil, using tin as a thermometric element. Secondly, a summation approach for two Absorption lines for aluminum falling within the same spectral window (305.5 – 309.5 nm) was evaluated. This approach improves the sensitivity without requiring any additional preconcentration steps. The third application describes a background subtraction technique, as it is applied to the analysis of an oil emulsion sample. Finally, interference effects caused by Na on the atomization of Pb were studied. The simultaneous measurements of Pb and Na suggests that negative interference arises at least partially from competition between Pb and Na atoms for H2 in the gas phase.
A Rowland Circle, multielement graphite furnace Atomic Absorption SpectrometerSpectrochimica Acta Part B: Atomic Spectroscopy, 1998Co-Authors: Karla. Wagner, James D. Batchelor, Bradley T. JonesAbstract:
Abstract A simultaneous, multielement Atomic Absorption Spectrometer utilizing a graphite furnace atomizer was constructed and evaluated. The optical arrangement employs a concave grating to combine the spectral output from a deuterium lamp and four hollow cathode lamps that are placed on the perimeter of a Rowland Circle. A graphite furnace atomizer is positioned on the circle at the point of convergence of the five light sources. Background correction is performed by the continuum source method. Simultaneous detection of the analyte Absorption signals is accomplished with a charged-coupled device. Four test elements were used for evaluation purposes: cadmium, lead, copper and chromium. Even though the elements differ greatly in volatility, the detection limits approach the values published for single element GFAAS: 4, 12, 14 and 12 pg for Cd, Pb, Cu and Cr, respectively. The characteristic masses (integrated absorbance) for the four metals are 3, 24, 14 and 7 pg, respectively. Three drinking water reference materials are analyzed: NIST SRM #1643b (Trace Elements in Water), Fisher Scientific “Metals Drinking Water Standard,” and High Purity Standards “Drinking Water Metals Solution A and B”. The determined amounts were within 10% of the certified values for each of the four elements for all three reference materials.
Yu. V. Rogul’skii – One of the best experts on this subject based on the ideXlab platform.
Tungsten-assisted modification of graphite furnaces for an Atomic Absorption SpectrometerJournal of Applied Spectroscopy, 2009Co-Authors: A. N. Kulik, A. N. Bugai, Yu. V. Rogul’skii, T. G. KalinichenkoAbstract:
We have used scanning electron microscopy to study changes in the morphology of the inner surface of graphite tube furnaces for an Atomic Absorption Spectrometer when modified by tungsten. We have demonstrated the role of the tungsten-containing material as a dividing interlayer between the sample to be dispensed and the carbon component of the furnace. We consider the advantages and disadvantages of furnaces modified by the proposed methods.
Effect on silicon atomization of tungsten-assisted modification of Atomic–Absorption Spectrometer graphite furnacesJournal of Applied Spectroscopy, 2008Co-Authors: A. N. Kulik, A. N. Buhay, Yu. V. Rogul’skiiAbstract:
The influence of a tungsten-assisted modification to a tubular graphite furnace in an Atomic Absorption Spectrometer on the Si atomization signal characteristics is studied. A hypothesis is proposed that explains a shift of Si atomization peaks for the modified furnaces compared with the standard ones. Some advantages of the standard tubular graphite furnaces modified by tungsten and the prospects for their application are demonstrated.
EFFECT OF WEAR OF THE Atomic–Absorption Spectrometer GRAPHITE FURNACE ON THE ANALYTICAL ZONE TEMPERATUREJournal of Engineering Physics and Thermophysics, 2007Co-Authors: A. N. Kulik, A. N. Bugai, Yu. V. Rogul’skii, M. I. Zakharets, Leonid F. SukhodubAbstract:
One mechanism of increase in the heating temperature of the analytical zone of the graphite tube furnace of the Atomic–Absorption Spectrometer as a result of wear is discussed. The influence of the furnace profile on its heating temperature is shown, and the calculated heating temperature of the standard tube is compared to the temperature in the special case where the cross-section area of the analytical zone of the furnace is reduced by half. Experimental proofs of a given temperature excess, as well as of a relation between the change in the tube profile and the decrease in its mass, are given. The dependence of temperature on the furnace mass and the number of measurements has been investigated. The necessity of taking into account the increase in the heating temperature of the furnace in the wear process has been considered.