Temporal Gating for the Optimization of Laser-Induced Breakdown Spectroscopy Detection and Analysis of Toxic Metals

2001 ◽  
Vol 55 (10) ◽  
pp. 1312-1319 ◽  
Author(s):  
Brian T. Fisher ◽  
Howard A. Johnsen ◽  
Steven G. Buckley ◽  
David W. Hahn
Keyword(s):  
Toxic Metals ◽  
Delay Time ◽  
Atomic Emission ◽  
Metal Species ◽  
Laser Induced Breakdown Spectroscopy ◽  
Experimental Conditions ◽  
Breakdown Spectroscopy ◽  
Select Group ◽  
Delay Times ◽  
Laser Induced Breakdown

Optimal temporal gating for laser-induced breakdown spectroscopy (LIBS) analysis was investigated for a select group of toxic metals, namely the Resource Conservation and Recovery Act (RCRA) metals arsenic, beryllium, cadmium, chromium, lead, and mercury. The differing rates of decay between the continuum plasma emission and the atomic emission were used as a means to maximize the signal-to-noise ratio of the atomic emission lines for these six metal species. Detection windows were investigated corresponding to delay times from 2 to 50 μs following the plasma-initiating laser pulse. For the current experimental conditions, it is concluded that the relatively short delay time of 12 μs is optimal for the detection of arsenic, beryllium, cadmium, and mercury, while a longer delay time of 50 μs is optimal for the detection of chromium and lead. The reduced atomic emission intensity at relatively long delay times is compensated for by the use of long detector gate widths. Estimated detection limits are reported for the six metal species based on the optimized temporal gating and ensemble averaging of multiple laser pulses, and the implications for simultaneous metals monitoring are discussed.

Influences on Concentration Measurements of Liquid Aerosols by Laser-Induced Breakdown Spectroscopy

1995 ◽  
Vol 49 (5) ◽  
pp. 569-579 ◽  
Author(s):  
Dana E. Poulain ◽  
Dennis R. Alexander
Keyword(s):  
Excimer Laser ◽  
Intensity Ratio ◽  
Droplet Diameter ◽  
Current Method ◽  
Atomic Emission ◽  
Laser Induced Breakdown Spectroscopy ◽  
Experimental Conditions ◽  
Probe Volume ◽  
Breakdown Spectroscopy ◽  
Laser Induced Breakdown

Results are presented for laser-induced breakdown spectroscopy (LIBS) as a method for measuring salt concentrations in seawater aerosol droplets. An excimer laser, operating at high pulse energy with KrF gas (λ = 248 nm) produces laser-induced breakdown plasmas in an aerosol spray. Emission lines of Na and H are monitored with an optical multichannel analyzer to characterize the plasma spatially and temporally. Studies of temporally resolved atomic line emissions from the plasma determine the optimum time for gating of the detector to be 2–4 μs after the excimer laser pulse arrives in the probe volume. Spatially resolved measurements of atomic emission line intensities are studied by positioning a stream of monodisperse droplets at various locations relative to the measurement probe volume. The electron temperature of the plasma is estimated to be 12,600 ± 4600 K, averaged over 1700 measurements during a 100-ns interval 2 μs after breakdown. Calibration curves are presented relating the Na(I) 589-nm to Hα 656.3-nm intensity ratio as a function of Na concentration, ranging from 100 to 10,000 ppm. Limits of detection for Na by the current method under the experimental conditions are estimated to be approximately 165 ppm for monodisperse sprays and 925 ppm for one case involving a polydisperse spray. Droplet diameter strongly influences the observed emission intensity ratio.

Laser-Induced Breakdown Spectroscopy Analysis of Lead Aerosol in Nitrogen and Air Atmosphere

2017 ◽  
Vol 72 (4) ◽  
pp. 584-590 ◽  
Author(s):  
Daniele A. Redoglio ◽  
Natascia Palazzo ◽  
Francesca Migliorini ◽  
Roberto Dondè ◽  
Silvana De Iuliis
Keyword(s):  
Laser Pulse ◽  
Delay Time ◽  
Plasma Temperature ◽  
Laser Induced Breakdown Spectroscopy ◽  
Experimental Conditions ◽  
Breakdown Spectroscopy ◽  
Air Atmosphere ◽  
Laser Induced Breakdown ◽  
Carrier Gases ◽  
Pb Concentration

In this work, laser-induced breakdown spectroscopy (LIBS) is applied for quantitative measurements of Pb in aerosols. In order to investigate the carrier gas role and, in particular, the effect of O2 addition to the gas itself, measurements are carried out in nitrogen and air atmosphere. Aerosol particles are produced by nebulizing Pb(CH3COO)2 * 3H2O aqueous solutions of known concentration and the atomic line of 405.8 nm is detected as Pb signature. The plasma generated with the laser pulse is characterized in terms of plasma temperature and electron density, showing no substantial differences with the two carrier gases used. The behavior of the LIBS signal as a function of the delay time with respect to the laser pulse is investigated changing the environmental conditions and, in particular, the Pb concentration values. The different trends registered in the case of relatively short (up to 20 μs) and long delay time, resulting to be the same whatever the Pb concentration value, could have a significant effect on the calibration curve performed in different experimental conditions.

Characterization of Amethysts from Sukamara, Central Kalimantan, Using Laser-Induced Breakdown Spectroscopy (LIBS)

2020 ◽  
Vol 1 (2) ◽  
pp. 5-8
Author(s):  
Komang Gde Suastika, Heri Suyanto, Gunarjo, Sadiana, Darmaji
Keyword(s):  
Emission Intensity ◽  
Laser Energy ◽  
Emission Spectra ◽  
Atomic Emission ◽  
Laser Induced Breakdown Spectroscopy ◽  
Chemical Formula ◽  
Central Kalimantan ◽  
Breakdown Spectroscopy ◽  
Laser Induced Breakdown

Abstract - Laser-Induced Breakdown Spectroscopy (LIBS) is one method of atomic emission spectroscopy using laser ablation as an energy source. This method is used to characterize the type of amethysts that originally come from Sukamara, Central Kalimantan. The result of amethyst characterization can be used as a reference for claiming the natural wealth of the amethyst. The amethyst samples are directly taken from the amethyst mining field in the District Gem Amethyst and consist of four color variations: white, black, yellow, and purple. These samples were analyzed by LIBS, using laser energy of 120 mJ, delay time detection of 2 μs and accumulation of 3, with and without cleaning. The purpose of this study is to determine emission spectra characteristics, contained elements, and physical characteristics of each amethyst sample. The spectra show that the amethyst samples contain some elements such as Al, Ca, K, Fe, Gd, Ba, Si, Be, H, O, N, Cl and Pu with various emission intensities. The value of emission intensity corresponds to concentration of element in the sample. Hence, the characteristics of the amethysts are based on their concentration value. The element with the highest concentration in all samples is Si, which is related to the chemical formula of SiO2. The element with the lowest concentration in all samples is Ca that is found in black and yellow amethysts. The emission intensity of Fe element can distinguish between white, purple, and yellow amethyst. If Fe emission intensity is very low, it indicates yellow sample. Thus, we may conclude that LIBS is a method that can be used to characterize the amethyst samples.Key words: amethyst, impurity, laser-induced, breakdown spectroscopy, characteristic, gemstones

scholarly journals Analysis of Garnet by Laser-Induced Breakdown Spectroscopy—Two Practical Applications

Minerals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 705
Author(s):  
Peter A. Defnet ◽  
Michael A. Wise ◽  
Russell S. Harmon ◽  
Richard R. Hark ◽  
Keith Hilferding
Keyword(s):  
Optical Emission ◽  
Atomic Emission ◽  
Laser Induced Breakdown Spectroscopy ◽  
Support Vector ◽  
Success Rates ◽  
Practical Applications ◽  
Chemical Complexity ◽  
Geochemical Fingerprinting ◽  
Breakdown Spectroscopy ◽  
Laser Induced Breakdown

Laser-induced breakdown spectroscopy (LIBS) is a simple and straightforward technique of atomic emission spectroscopy that can provide multi-element detection and quantification in any material, in-situ and in real time because all elements emit in the 200–900 nm spectral range of the LIBS optical emission. This study evaluated two practical applications of LIBS—validation of labels assigned to garnets in museum collections and discrimination of LCT (lithium-cesium-tantalum) and NYF (niobium, yttrium and fluorine) pegmatites based on garnet geochemical fingerprinting, both of which could be implemented on site in a museum or field setting with a handheld LIBS analyzer. Major element compositions were determined using electron microprobe analysis for a suite of 208 garnets from 24 countries to determine garnet type. Both commercial laboratory and handheld analyzers were then used to acquire LIBS broadband spectra that were chemometrically processed by partial least squares discriminant analysis (PLSDA) and linear support vector machine classification (SVM). High attribution success rates (>98%) were obtained using PLSDA and SVM for the handheld data suggesting that LIBS could be used in a museum setting to assign garnet type quickly and accurately. LIBS also identifies changes in garnet composition associated with increasing mineral and chemical complexity of LCT and NYF pegmatites.

Implementation of laser-induced breakdown spectroscopy as a continuous emissions monitor for toxic metals

2000 ◽  
Vol 20 (5-6) ◽  
pp. 455-462 ◽  
Author(s):  
Steven G. Buckley ◽  
Howard A. Johnsen ◽  
Kenneth R. Hencken ◽  
David W. Hahn
Keyword(s):  
Toxic Metals ◽  
Laser Induced Breakdown Spectroscopy ◽  
Breakdown Spectroscopy ◽  
Laser Induced Breakdown

The high dependence of polarization resolved laser-induced breakdown spectroscopy on experimental conditions

2012 ◽  
Vol 21 (7) ◽  
pp. 074204 ◽  
Author(s):  
Nakimana Agnes ◽  
Zuo-Qiang Hao ◽  
Jia Liu ◽  
Hai-Yan Tao ◽  
Xun Gao ◽  
...  
Keyword(s):  
Laser Induced Breakdown Spectroscopy ◽  
Experimental Conditions ◽  
Breakdown Spectroscopy ◽  
Laser Induced Breakdown

scholarly journals Laser-Induced Breakdown Spectroscopy of AL-Samples: Application to Chemical Analysis of Metallic Elementsf

1995 ◽  
Vol 16 (2) ◽  
pp. 75-82 ◽  
Author(s):  
B. Bescós ◽  
J. Castaño ◽  
A. González Ureña
Keyword(s):  
Chemical Analysis ◽  
Simultaneous Detection ◽  
Laser Induced Breakdown Spectroscopy ◽  
Minor Components ◽  
Experimental Conditions ◽  
Breakdown Spectroscopy ◽  
Non Invasive ◽  
Multichannel Analysis ◽  
Laser Induced Breakdown ◽  
On Line

This paper reports on the simultaneous detection of Mg, Mn, Fe and Pb in Al samples using laser-induced breakdown spectroscopy and optical multichannel analysis of the photoablated microplasma. Using calibrated samples, well characterized linear working curves were determined for these minor components over the 0.01–1% concentration range. In addition optimum experimental conditions were found that allow the analysis to be carded out in a fast and non-invasive manner. The potential application of the method to on-line industrial analysis is also suggested.

Sample Presentation Considerations in Laser-Induced Breakdown Spectroscopy in Aqueous Solution

2007 ◽  
Vol 61 (9) ◽  
pp. 1021-1024 ◽  
Author(s):  
Xiao Fang ◽  
S. Rafi Ahmad
Keyword(s):  
Elemental Analysis ◽  
Aqueous Media ◽  
Water Jet ◽  
Laser Induced Breakdown Spectroscopy ◽  
Signal To Noise ◽  
Experimental Conditions ◽  
Breakdown Spectroscopy ◽  
Laser Induced Breakdown ◽  
Sample Presentation ◽  
Presentation Methods

Various sample presentation configurations for elemental analysis in aqueous media by laser-induced breakdown spectroscopy (LIBS) have been tested and analyzed. Direct and quantitative comparison between the two different sample presentation methods, plasma excitation within water bulk and on the surface in a water jet, has been carried out using the same LIBS system under the same experimental conditions. Temporal characteristics of light emitted from the plasma induced in both the water bulk and the jet surface containing calcium (Ca) were recorded and presented. Spectral data recorded under optimum detection gating conditions showed that the signal-to-noise ratio (S/N) for excitation in the water jet configuration is approximately 10 times higher than that in the bulk excitation, the actual values of enhancement being dependent on the element type. The typical spectra of aqueous samples containing sodium (Na), calcium (Ca), zinc (Zn), cadmium (Cd), and mercury (Hg) were detected and the signal-to-noise ratios were evaluated and compared for the sample presentation configurations under considerations. The results suggest that for better sensitivity of detection, a simple water jet sample presentation configuration could be designed and implemented for cost-effective commercial use of this technique for elemental analysis in a water environment.

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