A locally built portable tungsten filament electrothermal atomic absorption spectrophotometer was used to develop a method for the determination of nickel. The instrument used a 150 W tungsten coil extracted from a commercial light bulb as an atomizer. The power supply for the instrument was varied whilst all other components of the instrument remained unchanged. The power supplies were operated in four different modes; current, power, voltage 1, and voltage 2. The modes were evaluated to identify which one yielded the best sensitivity. The methods of quantification of the results were integrated absorbance and peak height. The quantification method of our instrument was evaluated based on a mathematical model proposed by Sturgeon for a graphite furnace atomizer.
Voltage 2 had the fastest heating rate, it showed a heating rate of 3930 K/s, recorded the lowest limit of detection of 68.35 ± 0.0037 ng/mL for area and 71.9 ± 0.015 ng/mL for peak height with a sensitivity of 0.0705 ng/mL. It was the most sensitive of the four modes. Power, voltage 1 and current followed in order of decreasing sensitivities with sensitivity values of 0.078 ng/mL, 0.0859 ng/mL and 0.1055 ng/mL respectively. The limits of detection followed the same trend as the sensitivity. However, for the heating rate, voltage 1 was faster followed by power and finally current.
This paper's results were comparable to that proposed by Sturgeon in terms of effects of analyte concentration and the absorbance generated even though the atomizers and instruments setup were completely different.
|Commitee:||Jones, Myron, Patrick, Tim|
|School:||Southern Illinois University at Edwardsville|
|School Location:||United States -- Illinois|
|Source:||MAI 54/02M(E), Masters Abstracts International|
|Keywords:||Electrothermal atomizer, Nickel, Tungsten|
Copyright in each Dissertation and Thesis is retained by the author. All Rights Reserved
The supplemental file or files you are about to download were provided to ProQuest by the author as part of a
dissertation or thesis. The supplemental files are provided "AS IS" without warranty. ProQuest is not responsible for the
content, format or impact on the supplemental file(s) on our system. in some cases, the file type may be unknown or
may be a .exe file. We recommend caution as you open such files.
Copyright of the original materials contained in the supplemental file is retained by the author and your access to the
supplemental files is subject to the ProQuest Terms and Conditions of use.
Depending on the size of the file(s) you are downloading, the system may take some time to download them. Please be