- 标题
- 摘要
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- 实验方案
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Application of Scikit and Keras Libraries for the Classification of Iron Ore Data Acquired by Laser-Induced Breakdown Spectroscopy (LIBS)
摘要： Due to the complexity of, and low accuracy in, iron ore classification, a method of Laser‐Induced Breakdown Spectroscopy (LIBS) combined with machine learning is proposed. In the research, we collected LIBS spectra of 10 iron ore samples. At the beginning, principal component analysis algorithm was employed to reduce the dimensionality of spectral data, then we applied k‐nearest neighbor model, neural network model, and support vector machine model to the classification. The results showed that the accuracy of three models were 82.96%, 93.33%, and 94.07% respectively. The results also demonstrated that LIBS with machine learning model exhibits an excellent classification performance. Therefore, LIBS technique combined with machine learning can achieve a rapid, precise classification of iron ores, and can provide a completely new method for iron ores’ selection in the metallurgical industry.
关键词： machine learning,laser‐induced breakdown spectroscopy,iron ore,classification
更新于2025-09-16 10:30:52
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High-throughput analysis of single particles by micro laser induced breakdown spectroscopy
摘要： Multi-elemental analysis of particulate matters is highly desirable for the identification of their emission sources. However, the traditional techniques for single particle analysis usually require time-consuming sample preparation procedures. We report here a system that combines bright-field microscopy with laser induced breakdown spectroscopy (LIBS), allowing rapid and multi-elemental analysis of single particles. The improved throughput of the system was benefited from the use of ultra-thin polyethylene films for particle immobilization such that their spectra were collected successively. The simple composition of the films avoided their interferences in the particles’ LIBS spectra. Moreover, the small thickness of the films allowed their rapid vaporization during laser ablation such that the plasma emissions from the particles were not quenched by their substrates. The performances of the system were demonstrated by studying the heterogeneity in particles’ compositions and discriminating dust particles with very similar chemicals, suggesting that it is a promising tool for environmental risk assessment.
关键词： single particles,Laser induced breakdown spectroscopy,high-throughput
更新于2025-09-16 10:30:52
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Laser-induced breakdown spectroscopy for food authentication
摘要： With the globalisation of food markets, food authentication has become a significant concern worldwide to ensure food safety and to avoid origin and quality fraud. A multi-elemental fingerprint is a powerful tool for detection of adulterants and geographical origin of foods. Laser-induced breakdown spectroscopy (LIBS) is a promising technique that can provide a mineral fingerprint of food products. LIBS allows a rapid, high-throughput, micro-destructive and multi-elemental analysis of a wide range of samples type. It has already been demonstrated by several authors that LIBS can be successfully used for food authentication. Although LIBS shows excellent potential for at-line or portable applications, improvement in sensitivity of trace elements detection, sample preparation, data analysis and instrument miniaturisation are needed.
关键词： LIBS,Laser-induced breakdown spectroscopy,multi-elemental analysis,food authentication,fraud detection
更新于2025-09-16 10:30:52
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Spatial Molecular AlO Temperature Distributions in Laser-Induced Plasma
摘要： Spatially resolved, line-of-sight measurements of aluminum monoxide emission spectra in laser ablation plasma are used with Abel inversion techniques to extract radial plasma temperatures. Contour mapping of the radially deconvolved signal intensity shows a ring of AlO formation near the plasma boundary with the ambient atmosphere. Simulations of the molecular spectra were coupled with the line profile fitting routines. Temperature results are presented with simultaneous inferences from lateral, asymmetric radial, and symmetric radial AlO spectral intensity profiles. This analysis indicates that shockwave phenomena in the radial profiles, including a temperature drop behind the blast wave created during plasma initiation were measured.
关键词： laser-induced plasma,Abel transform,plasma spectroscopy,molecular spectroscopy,plasma dynamics,laser-induced breakdown spectroscopy,diatomic spectroscopy
更新于2025-09-12 10:27:22
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Investigation of excitation interference in laser-induced breakdown spectroscopy assisted with laser-induced fluorescence for chromium determination in low-alloy steels
摘要： Chromium determination in steels suffered from excitation interference in laser-induced breakdown spectroscopy assisted with laser-induced fluorescence (LIBS-LIF). In this work, excitation interference between target chromium atoms and matrix iron atoms was investigated in detail. Relative absorption strength (RAS) of chromium and iron was mathematically deduced and utilized to estimate the excitation interference theoretically. Standard calibration curves of LIBS and LIBS-LIF for chromium determination in low-alloy steels were experimentally established. The chromium line 359.35 nm with less interference in the RAS map provided better analytical performance (slope of 1.99 ×10 5 counts/ wt%, detection limit of 8.64 μg g ? 1 , R 2 of 0.992, average RSD of 2.89%), in accordance with the theoretical estimation. This work realized sensitive and accurate determination of trace chromium in low-alloy steels, even influenced by excitation interference. An effective estimation method was provided for evaluating excitation interference to choose a suitable excitation line.
关键词： Laser-induced fluorescence,Steel,Excitation interference,Chromium,Laser-induced breakdown spectroscopy
更新于2025-09-12 10:27:22
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[IEEE 2019 Wave Electronics and its Application in Information and Telecommunication Systems (WECONF) - Saint-Petersburg, Russia (2019.6.3-2019.6.7)] 2019 Wave Electronics and its Application in Information and Telecommunication Systems (WECONF) - Analysis of Hpht Diamonds by Laser-Induced Breakdown Spectroscopy
摘要： The analysis of sectoral nitrogen-containing HPHT diamonds by the method of laser-induced breakdown spectroscopy was performed. The possibility of detecting changes in structural bonds and the impurity composition under conditions of laser- induced graphitization of the surface was studied. It was found that the plasma spectra of transition states of the surface during the process of laser-induced graphitization are also very important for analysis and can help identification of diamonds. the Identification of diamonds can occur both based on detecting differences in the content of H, O, N impurities, and detecting differences in the structural disorder of carbon bonds, particularly in the relative change in the number of C=C bonds. All these differences may be a consequence of either technological differences in the history of diamond synthesis, or the presence of additional post-growth diamond processing, or with the presence of the multisectoral structure of the test sample
关键词： HPHT diamonds,laser-induced breakdown spectroscopy,laser-induced graphitization
更新于2025-09-12 10:27:22
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Characterization of the Chinese Traditional Medicine <i>Artemisia annua</i> by Laser-Induced Breakdown Spectroscopy (LIBS) with 532?nm and 1064?nm Excitation
摘要： In order to investigate the influence of laser wavelength on the detection of the metals in Artemisia annua, pulsed lasers operating at wavelengths of 1064 nm and 532 nm for laser-induced breakdown spectroscopy (LIBS) have been employed to generate the plasma. The spectral lines of Mg (II) at 279.54 nm, CN at 388.29 nm, Ca (II) at 393.37 nm and Fe (II) at 404.27 nm were used to evaluate the optical emission at various delay times for the 532 nm and the 1064 nm laser. The effects of the data acquisition delay time on the line intensity, signal-to-background ratio and the characteristic parameters of laser plasma have been investigated as well. The results show that the 1064 nm beam induced plasmas with higher signal-to-background ratios and temperatures than the 532 nm beam. However, the 532 nm laser beam produced plasma with higher electron densities than the 1064 nm laser beam. In addition, a significant influence has been found: the spectral intensities of the ions were stronger than the spectral intensities of the atoms independent of whether the laser was operated at 532 nm or 1064 nm.
关键词： laser induced plasma,Artemisia annua,laser induced breakdown spectroscopy (LIBS)
更新于2025-09-12 10:27:22
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Determination of Major Inorganic Nutrients in Maize Tissues by Calibration-Free Laser Induced Breakdown Spectroscopy
摘要： The quality of the available food is the main issue in the developing countries and maize is one of the commonly used foodstuffs in these countries. Laser-induced breakdown spectroscopy (LIBS) was employed to characterize the presence of the major inorganic nutrients in the maize samples. Each of the samples was shown to contain following elements: K, Ca, Mg, Fe, Na, Si, Li, Sr, Ti, Al, and C while Cr was only detected in the seeds. The electron number density was evaluated by the use of the Stark broadened profile of calcium line and the plasma temperatures have been determined using the Boltzmann plot method. Calibration-free LIBS (CF-LIBS) has been used for the quantitative elemental analysis of the samples. The consistency of the concentrations determined by CF-LIBS was validated using inductively coupled plasma – optical emission spectroscopy (ICP-OES).
关键词： calibration-free laser–induced breakdown spectroscopy (CF-LIBS),Maize,Plasma parameters,inductively coupled plasma–optical emission spectroscopy (ICP-OES)
更新于2025-09-12 10:27:22
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A multi-spot laser induced breakdown spectroscopy system based on diffraction beam splitter
摘要： A quick simultaneous multispot laser induced breakdown spectroscopy (LIBS) system has been proposed. The basic idea is to combine the Diffraction Beam Splitter (DBS) with the linear-to-linear fiber bundle. The DBS divided the incident laser beam into five sub-beams, and then, a lens focused the incident sub-beam to produce a plasma array, where the distance between the neighbor subplasma was constant and the plasma emission was imaged on the fiber bundle. Each ablated spot on the sample generated the corresponding spectroscopy signals, which were collected by the defined fibers of the fiber bundle, propagated to the spectrograph slit, and then analyzed by the intensified charge-coupled device (ICCD) detector, where the two-dimensional capability of the charge-coupled device detectors was explored for the spectroscopy and position analyses. The five spectroscopy ribbon presented on the ICCD corresponded to the plasma radiation of the five ablated spots. The feasibility of a simultaneous multipoint spectroscopy detection at a single pulse ablation was confirmed by subjecting to the spectroscopy analyses of a copper plane, layered material, and magnesium-molybdenum mixture. The multispot LIBS system can be used in the ejecta research of detonation physics, fluid physics, and so on.
关键词： laser induced breakdown spectroscopy,spectroscopy analysis,multispot,LIBS,DBS,diffraction beam splitter,plasma array
更新于2025-09-12 10:27:22
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Discrimination of wood species using laser-induced breakdown spectroscopy and near-infrared reflectance spectroscopy
摘要： A new method is proposed for the discrimination of wood species by combining near-infrared reflectance spectroscopy (NIRS) and laser-induced breakdown spectroscopy (LIBS) and using chemometrics for data analysis. The method was applied to the analysis of 42 samples from six different species: Amburana cearensis, Copaifera lucens, Phyllocarpus riedelii, Cariniana legalis, Bowdichia virgilioides, and Aspidosperma pyricollum. The spectra from both techniques were merged on a single data matrix and pretreated by standard normal variate (SNV) and Savitzky– Golay first derivative with smoothing. Principal component analysis was applied to the exploratory data analysis and showed a clear formation of sample groups according to the wood species only when the data from both analytical techniques and the data pretreatment were used. Sample discrimination using partial least squares discriminant analysis was proved possible, but with an average misclassification of about 10%. Sample grouping and discrimination were shown to be probably related to different concentrations of iron, copper, zinc, and/or sodium (affecting the LIBS spectra) and lignin, water, cellulose, and/or hemicellulose (affecting the NIRS spectra).
关键词： wood species discrimination,laser-induced breakdown spectroscopy,near-infrared reflectance spectroscopy,chemometrics
更新于2025-09-12 10:27:22