Experimental and Theoretical Comparison of the Precision of Flame Atomic Absorption, Fluorescence, and Emission Measurements

1981 ◽  
Vol 35 (3) ◽  
pp. 317-324 ◽  
Author(s):  
N. W. Bower ◽  
J. D. Ingle
Keyword(s):  
Atomic Absorption ◽  
Flicker Noise ◽  
Power Spectra ◽  
Inner Filter Effect ◽  
Atomic Emission ◽  
Noise Power ◽  
Experimental Conditions ◽  
Noise Characteristics ◽  
Fluorescence Measurements ◽  
Flame Atomic Absorption

Theoretical equations and experimental evaluation procedures for the determination of the precision of flame atomic absorption, emission, and fluorescence measurements are presented. These procedures and noise power spectra are used to evaluate the precision and noise characteristics of atomic copper measurements with all three techniques under the same experimental conditions in an H2-air flame. At the detection limit, emission and fluorescence measurements are limited by background emission shot and flicker noise whereas absorption measurements are limited by flame transmission lamp flicker noise. Analyte flicker noise limits precision at higher analyte concentrations for all three techniques. Fluctutations in self-absorption and the inner filter effect are shown to contribute to the noise in atomic emission and fluorescence measurements.

Current-Noise-Power-Spectra for Amorphous Silicon Photodiode Sensors

1993 ◽  
Vol 297 ◽  
Author(s):  
J.M. Boudry ◽  
L.E. Antonuk
Keyword(s):  
Amorphous Silicon ◽  
Flicker Noise ◽  
Field Effect Transistors ◽  
Power Spectra ◽  
Current Noise ◽  
Noise Power ◽  
Silicon Photodiode ◽  
Noise Characteristics ◽  
X Ray Imaging ◽  
Array Performance

Pixelated imaging arrays consisting of hydrogenated amorphous silicon (a-Si:H) photodiode sensors and field effect transistors are under development for x-ray imaging. For such arrays it is important to quantify the sensor noise characteristics as these may, in some cases, limit the array performance for certain applications. The current-noise-power-spectra of ∼1 nm thick a- Si:H p-i-n sensors of various areas are presented. The power spectra were measured for different reverse bias voltages over a frequency range of ∼0.01 to 1.0 Hz. The power spectra revealed the noise to be composed primarily of flicker noise. The flicker noise showed a l/fbdependence where b ranged from ∼1.1 to 1.2. The magnitude of the flicker noise as a function of the sensor leakage current and the sensor area has been investigated and is presented.

scholarly journals Determination of cobalt in water samples by atomic absorption spectrometry after pre-concentration with a simple ionic liquid-based dispersive liquid-liquid micro-extraction methodology

2010 ◽  
Vol 8 (3) ◽  
pp. 617-625 ◽  
Author(s):  
Hossein Abdolmohammad-Zadeh ◽  
Elnaz Ebrahimzadeh
Keyword(s):  
Ionic Liquid ◽  
Atomic Absorption Spectrometry ◽  
Atomic Absorption ◽  
Water Samples ◽  
Limit Of Detection ◽  
Absorption Spectrometry ◽  
Experimental Conditions ◽  
Flame Atomic Absorption ◽  
Relative Standard

AbstractA rapid dispersive liquid-liquid micro-extraction (DLLME) methodology based on the application of 1-hexylpyridinium hexafluorophosphate [C6py][PF6] ionic liquid (IL) as an extractant solvent was applied for the pre-concentration of trace levels of cobalt prior to determination by flame atomic absorption spectrometry (FAAS). 1-Phenyl-3-methyl-4-benzoyl-5-pyrazolone (PMBP) was employed as a chelator forming a Co-PMBP complex to extract cobalt ions from aqueous solution into the fine droplets of [C6py][PF6]. Some effective factors that influence the micro-extraction efficiency include the pH, the PMBP concentration, the amount of ionic liquid, the ionic strength, the temperature and the centrifugation time which were investigated and optimized. In the optimum experimental conditions, the limit of detection (3s) and the enrichment factor were 0.70 µg L−1 and 60, respectively. The relative standard deviation (RSD) for six replicate determinations of 50 µg L−1 Co was 2.36%. The calibration graph using the pre-concentration system was linear at levels 2–166 µg L−1 with a correlation coefficient of 0.9982. The applicability of the proposed method was evaluated by the determination of trace amounts of cobalt in several water samples.

Hydride Generation and Condensation Flame Atomic Absorption Spectroscopic Determination of Antimony in Raw Coffee Beans and Processed Coffee

1982 ◽  
Vol 65 (5) ◽  
pp. 1146-1149
Author(s):  
Roy W Kuennen ◽  
Mark H Hahn ◽  
Fred L Fricke ◽  
Karen A Wolnik
Keyword(s):  
Atomic Absorption ◽  
Inductively Coupled Plasma ◽  
Hydride Generation ◽  
Dry Weight ◽  
Atomic Emission ◽  
Standard Reference Materials ◽  
National Bureau ◽  
Total Acid ◽  
Flame Atomic Absorption ◽  
Coffee Beans

Abstract A method was developed for determining Sb at nanogram per gram levels in raw coffee beans and processed coffee. The procedure uses either total acid digestion or extraction with 6M HCl followed by hydride generation/condensation with subsequent revolatilization of stibine (SbH3) and detection by flame atomic absorption spectroscopy. The lowest quantifiable level, based on a 2 g (dry weight) sample, is 2 ng Sb/g. The results of recoveries on spiked samples, precision studies on composited coffee samples, and the analysis of National Bureau of Standards Standard Reference Materials demonstrate the reliability and accuracy of the procedure. Sb concentrations in coffee samples were verified by neutron activation analysis and inductively coupled plasma atomic emission spectroscopy. Advantages of the method compared with the AOAC colorimetric procedure and hydride generation without condensation are discussed.

Influence of Phosphorus and Calcium on Flame Atomic Absorption Spectrophotometric Determination of Lead in Canned Fish Products

1984 ◽  
Vol 67 (1) ◽  
pp. 186-187
Author(s):  
Teresa M Serra ◽  
J F Vale Serrano
Keyword(s):  
Atomic Absorption ◽  
Atomic Absorption Spectrophotometry ◽  
Flame Atomic Absorption Spectrophotometry ◽  
Experimental Conditions ◽  
Fish Products ◽  
Real Samples ◽  
Absorption Spectrophotometry ◽  
Flame Atomic Absorption ◽  
Canned Fish

Abstract Lead was determined in the presence of whole multiples of the P/Ca ratio found in Portuguese canned fish by flame atomic absorption spectrophotometry with and without using an ashing aid. Under our experimental conditions, use of the ashing aid eliminates P and Ca interference. Results with real samples, spiked with 1, 2,3, and 4 ppm lead, are presented and statistically treated.

An Experimental Study of Lithium Furnace Emission

1978 ◽  
Vol 32 (1) ◽  
pp. 54-56 ◽  
Author(s):  
J. P. Matousek ◽  
L. E. Smythe
Keyword(s):  
Atomic Absorption ◽  
Graphite Furnace ◽  
Growth Curves ◽  
Atomic Emission ◽  
Diagnostic Techniques ◽  
Atomic Absorption Spectrometer ◽  
Signal To Noise ◽  
Absorption Signal ◽  
Noise Characteristics ◽  
Low Levels

Atomic emission of lithium in a small graphite furnace (CRA 63) was observed using a standard atomic absorption spectrometer with simple optical modifications. Improved diagnostic techniques facilitated a study of lithium atomic emission and atomic absorption signal profiles as a function of temperature. Low levels of lithium were measured relatively free from background emission with considerably improved signal-to-noise characteristics. Analytical growth curves plotted in logarithmic coordinates showed only a slight deviation from linearity over a concentration range of three orders.

Sign in / Sign up

Export Citation Format

Share Document