Article
Spectroscopy
Jonathan Merten, Erin Nicholas, Shealyn Chestnut, Shawnda Ethridge, Hannah Bariola, Mary Elizabeth Foster
Summary: The absolute atomized mass of a laser-induced yttrium plasma was measured under various noble and oxidizing cover gases using high resolution atomic-absorption spectroscopy mapping. The maximum spatial extent of the plasma decreased with the molar mass of the cover gas. Time-resolved masses measured under oxidizing atmospheres showed continuous net loss from the first measured delay. Plasmas under helium and argon atmospheres also exhibited net loss of atomized yttrium beyond 4 mu s, due to an unknown mechanism.
SPECTROCHIMICA ACTA PART B-ATOMIC SPECTROSCOPY
(2023)
Article
Chemistry, Analytical
Fangjian Zhang, Qiuyun Wang, Yuanfei Jiang, Anmin Chen, Mingxing Jin
Summary: Metal nanoparticles (NPs) at different concentrations were deposited on the pure Al substrate surface to enhance the spectral emission of AlO molecular bands. The emission intensity of AlO (0-0) and (1-1) increased and then decreased with the increase of Au NP concentration, reaching the strongest emission at 0.98 ng mL(-1). The time-resolved characteristics of AlO spectra showed different emission intensities and spectral lifetimes at different concentrations of Au NPs, with the strongest peak intensity and longest spectral lifetime observed at 0.98 ng mL(-1) concentration. The vibration temperature of AlO was consistent with the spectral emission and varied with the concentration of Au NPs.
JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY
(2023)
Article
Optics
Eshita Mal, Rajendhar Junjuri, Manoj Kumar Gundawar, Alika Khare
Summary: The study investigated the laser-induced plasma (LIP) of molybdenum through time and space resolved laser-induced breakdown spectroscopy (LIBS) in air, revealing that plasma temperature and electron density decrease with increasing delay time but increase with increasing laser energy.
APPLIED PHYSICS B-LASERS AND OPTICS
(2021)
Article
Spectroscopy
Shangyong Zhao, Yuchen Zhao, Zongyu Hou, Zhe Wang
Summary: The polarization-resolved LIBS (PR-LIBS) and partial least squares (PLS) regression models were proposed to improve the stability and accuracy of qualitative and quantitative analysis of steel alloy elements. The relationship between the spectral intensity and the certified concentration information of steel alloy samples was modeled using PLS. PR-LIBS showed decreased relative standard deviation (RSD) and root-mean-square error (RMSE), and increased signal-to-background ratio (SBR) and co-efficient of determination (R2) compared to LIBS measurements. Quantitative results of Si, Mn, Cr, and Ni in steel alloy samples using PLS were displayed and discussed. For the PR-LIBS dataset, R2 has increased by at least 3.4%, and the root mean square error of calibration (RMSEC) and root mean square error of prediction (RMSEP) have improved by at least 6.3% and 19.0%, respectively. PR-LIBS is a simple and low-cost solution that can increase the stability and accuracy of LIBS measurements.
SPECTROCHIMICA ACTA PART B-ATOMIC SPECTROSCOPY
(2023)
Article
Chemistry, Analytical
Carl Basler, Moritz Kappeler, Daniel Carl
Summary: This study proposes a new method for inline measurement of depth profiles on a continuously moving sample using laser-induced breakdown spectroscopy. The ablation profile is generated by laser pulses, and the emission spectrum of each laser-induced plasma is analyzed. Feasibility for depth-resolved elemental analysis on moving samples is shown for coatings of electrode foils for lithium-ion batteries.
Article
Chemistry, Analytical
Zelin Liu, Guomin Zhao, Chuan Guo, Lei Chen, Minsun Chen, Hao Liu, Kai Han
Summary: This article presents an analytical method to validate local thermodynamic equilibrium in laser-induced plasmas, using a more universal function than the Maxwellian electron energy distribution function. The method estimates the evolution of the thermodynamic state in plasma by analyzing the actual EEDF of electrons at different positions. The consistency of similar EEDFs derived from emission lines associated with differently charged ions justifies the method as a reasonable LTE criterion.
JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY
(2021)
Article
Instruments & Instrumentation
David M. Surmick, Leon Taleh, Noureddine Melikechi
Summary: The impact of altering laser focusing conditions on laser-induced breakdown spectroscopy experiments was investigated in both ambient Earth laboratory and simulated Martian atmospheres. Results showed that the peak emissions of ionic species occur when the laser plasma is initiated with a focused spot within the sample in ambient Earth laboratory air, while atomic emissions have peak intensities several millimeters deeper into the sample. In simulated Martian atmospheres, atomic emissions peak when the laser is focused within the sample, while ionic emissions have peak intensities near the surface of the sample.
APPLIED SPECTROSCOPY
(2021)
Article
Spectroscopy
Xiangjun Xu, Qianqian Wang, Geer Teng, Zhifang Zhao, Kai Wei
Summary: This paper proposes a polarization spectral data fusion scheme to obtain richer spectral information and improve the performance of quantitative analysis models. By analyzing the polarization effect of laser-induced coal plasma emission, a fusion model utilizing horizontal and vertical polarization spectra is established for high prediction accuracy.
SPECTROCHIMICA ACTA PART B-ATOMIC SPECTROSCOPY
(2023)
Article
Chemistry, Analytical
Ismail Elhamdaoui, Nessrine Mohamed, Samira Selmani, Paul Bouchard, Mohamad Sabsabi, Marc Constantin, Francois Vidal
Summary: This paper discusses the use of conventional LIBS and LIBS-LIF techniques for measuring trace amounts of palladium in solid ore samples. The study optimized the performances of LIBS-LIF for spectrochemical analysis of palladium by studying the combination of excitation/fluorescence of Pd lines and plasma creation conditions. Calibration curves were established using reference materials doped with a palladium solution. The results demonstrated that LIBS-LIF could rapidly measure sub-ppm levels of palladium in solid ore samples without any sample preparation, and it could resolve the spectral interference which is problematic with conventional LIBS.
JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY
(2022)
Article
Chemistry, Analytical
Ran Zhou, Ke Liu, Zhiyang Tang, Zhongqi Hao, Xiangyou Li, Xiaoyan Zeng
Summary: In this study, the LIBS-LIF method was introduced to determine essential micronutrient elements in soil with high accuracy and sensitivity, showing promising results for future applications in soil nutrition evaluation.
JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY
(2021)
Article
Chemistry, Analytical
Yujia Dai, Chao Song, Xun Gao, Anmin Chen, Zuoqiang Hao, Jingquan Lin
Summary: Al-Cu-Mg-Fe-Ni aluminum alloy is a crucial aerospace equipment material, and the combination of LIBS technology with machine learning shows potential in accurately determining minor elements in the alloy. By establishing a multivariate quantitative analysis model, it can be applied for metal composition detection in aerospace equipment.
JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY
(2021)
Article
Food Science & Technology
Honghua Ma, Shengqun Shi, Deng Zhang, Nan Deng, Zhenlin Hu, Jianguo Liu, Lianbo Guo
Summary: A novel detection method based on time-resolved laser-induced breakdown spectroscopy (TR-LIBS) is proposed to accurately identify adulterants in brown rice flour. By using traditional machine learning and deep learning models, the classification accuracy of adulterants is significantly increased, and the performance of quantitative analysis is improved. These results demonstrate the importance of this method in the identification of adulteration in brown rice flour.
Article
Optics
Shuang Lin, Dan Zhang, Yuanfei Jiang, Anmin Chen, Mingxing Jin
Summary: This paper experimentally studied the propagation distance-resolved characteristics of copper plasma emission induced by axicon-focused femtosecond laser filamentation in the air. The results showed that Bessel beams generate more stable spectral intensity compared to Gaussian beams. The changes in plasma temperature and electron density along the filament propagation path are consistent with the change in spectral intensity.
Article
Chemistry, Analytical
Hai-Li Zhao, Lian-Lian CAI, Gang Wu
Summary: In this study, polarization resolved laser induced breakdown spectroscopy (PRLIBS) was combined with the support-vector regression (SVR) algorithm for Cd determination in soil. Soil samples were compressed and PRLIBS data on the surface of soil samples were collected as input data to establish calibration-curve models for quantitative analysis. The results showed that PRLIBS combined with SVR was suitable for Cd detection in soils with good detection effect.
CHINESE JOURNAL OF ANALYTICAL CHEMISTRY
(2023)
Article
Chemistry, Analytical
Nai-Ho Cheung
Summary: PLIF spectra need to be properly normalized for reliable analytical results. Standard normalization schemes can effectively reduce spectral fluctuations caused by extrinsic variations. However, complications like spectral features from two-photon absorption and extrinsic variations affecting spectral lineshapes may compromise normalization.
JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY
(2021)
