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High Resolution Phonon-assisted Quasi-resonance Fluorescence Spectroscopy
Published on: June 28, 2016
Background correction by wavelength modulation for pulsed-laser-excited atomic fluorescence spectrometry
Analytical Chemistry
|August 1, 1992
Summary
A new method uses wavelength modulation (WM) in laser-excited atomic fluorescence spectrometry (LEAFS) to correct for background noise. This technique effectively removes interference from flames, furnaces, and matrix particles, improving analytical accuracy.
Area of Science:
- Analytical Chemistry
- Spectroscopy
- Atomic Fluorescence
Background:
- Laser-excited atomic fluorescence spectrometry (LEAFS) can suffer from various background signals.
- Effective background correction is crucial for accurate quantitative analysis.
Purpose of the Study:
- To develop and demonstrate a novel wavelength modulation (WM) technique for background correction in LEAFS.
- To assess the performance of WM in correcting for different types of spectral interferences.
Main Methods:
- Constructed instrumentation to modulate dye laser wavelength using a piezoelectric pusher.
- Synchronized laser pulses for on-line (signal+background) and off-line (background) measurements.
- Calculated background-corrected signal by subtracting off-line from on-line measurements.
Main Results:
- Demonstrated effective background correction for flame emission, graphite furnace blackbody radiation, and matrix particle scatter.
- Achieved accurate determination of sodium in standard reference materials.
- WM technique showed good agreement with certified values.
Conclusions:
- Wavelength modulation is a robust and effective method for background correction in LEAFS.
- The technique is applicable to various tunable lasers and sample matrices.
- Improved accuracy in atomic fluorescence analysis through effective background suppression.
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