Pub Date : 2026-02-01Epub Date: 2025-12-24DOI: 10.1016/j.sab.2025.107309
Yi You , Boyang Xue , Jens Riedel
Laser-induced breakdown spectroscopy (LIBS) offers versatile, field-deployable elemental analysis; however, compact, high-repetition-rate nanosecond laser systems typically face constraints in power consumption and size, often compromising emission intensity and thus analytical performance. We demonstrate a significant improvement in LIBS signals through the controlled introduction of common organic solvent vapors into a sheath gas, with a diode-pumped solid-state laser (1064 nm, 2–28 kHz repetition rate, 450–600-μJ pulse energy). Optical and acoustic diagnostics reveal up to ca. 40-fold enhancement of the N II emission line at 567 nm when ambient air serves as the analyte. Maximal enhancement occurs at intermediate repetition rates of ca. 15 kHz, particularly at pulse energies approaching the optical breakdown threshold; this observation suggests a viable strategy for operating LIBS at lower pulse energies and higher repetition rates. Enhancement effects scale jointly with both vapor pressure and ionization energy of the organic species, with acetone and toluene markedly outperforming methanol and isopropanol. These findings provide a rational foundation for significantly improving the analytical performance of portable LIBS instruments without exceeding platform-specific constraints.
{"title":"Enhancement of LIBS plasma in air with organic solvent vapors","authors":"Yi You , Boyang Xue , Jens Riedel","doi":"10.1016/j.sab.2025.107309","DOIUrl":"10.1016/j.sab.2025.107309","url":null,"abstract":"<div><div>Laser-induced breakdown spectroscopy (LIBS) offers versatile, field-deployable elemental analysis; however, compact, high-repetition-rate nanosecond laser systems typically face constraints in power consumption and size, often compromising emission intensity and thus analytical performance. We demonstrate a significant improvement in LIBS signals through the controlled introduction of common organic solvent vapors into a sheath gas, with a diode-pumped solid-state laser (1064 nm, 2–28 kHz repetition rate, 450–600-μJ pulse energy). Optical and acoustic diagnostics reveal up to ca. 40-fold enhancement of the N II emission line at 567 nm when ambient air serves as the analyte. Maximal enhancement occurs at intermediate repetition rates of ca. 15 kHz, particularly at pulse energies approaching the optical breakdown threshold; this observation suggests a viable strategy for operating LIBS at lower pulse energies and higher repetition rates. Enhancement effects scale jointly with both vapor pressure and ionization energy of the organic species, with acetone and toluene markedly outperforming methanol and isopropanol. These findings provide a rational foundation for significantly improving the analytical performance of portable LIBS instruments without exceeding platform-specific constraints.</div></div>","PeriodicalId":21890,"journal":{"name":"Spectrochimica Acta Part B: Atomic Spectroscopy","volume":"236 ","pages":"Article 107309"},"PeriodicalIF":3.8,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145814369","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-02-01Epub Date: 2025-12-24DOI: 10.1016/S0584-8547(25)00322-2
{"title":"Outside Front Cover - Journal name, Cover image, Volume issue details, ISSN, Cover Date, Elsevier Logo and Society Logo if required","authors":"","doi":"10.1016/S0584-8547(25)00322-2","DOIUrl":"10.1016/S0584-8547(25)00322-2","url":null,"abstract":"","PeriodicalId":21890,"journal":{"name":"Spectrochimica Acta Part B: Atomic Spectroscopy","volume":"236 ","pages":"Article 107437"},"PeriodicalIF":3.8,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145814334","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-02-01Epub Date: 2025-12-24DOI: 10.1016/j.sab.2025.107307
Isabel Abad-Alvaro, Eduardo Bolea, Francisco Laborda
Performance of single particle inductively coupled plasma mass spectrometry (SP-ICP-MS) methods is constrained by the characteristics of the instrumentation. The commercial availability of fast data acquisition quadrupole instruments, which allow the use of dwell times in the microsecond range rather than being restricted to milliseconds, was expected to improve the performance of the technique. When data acquisition frequency is increased, individual particles are recorded as transient signals consisting of multiple-reading events instead of one-reading pulses. Since particle events must be detected above the baseline noise, the highest intensity reading of a transient signal becomes a relevant parameter whose value decreases with decreasing dwell time, as the total intensity of a particle event is independent of the number of readings per event and thus of the selected dwell time. In this work, the effect of dwell time on the attainable size detection limits has been reconsidered, achieving minimum size detection limits when dwell times in the range of 200–500 μs were used, regardless of the baseline level. At such dwell times, particle events from small nanoparticles (e.g., 2–3 times the size detection limit) were recorded within 1–2 readings despite the duration of particle events, which was modified working in both standard and gas reaction modes. Under these conditions, free and proprietary software capable of handling multiple-reading events allowed to process successfully the SP-ICP-MS data independently of the dwell time applied.
{"title":"Size detection limits in single particle inductively coupled plasma mass spectrometry: Reconsidering the selection of dwell times","authors":"Isabel Abad-Alvaro, Eduardo Bolea, Francisco Laborda","doi":"10.1016/j.sab.2025.107307","DOIUrl":"10.1016/j.sab.2025.107307","url":null,"abstract":"<div><div>Performance of single particle inductively coupled plasma mass spectrometry (SP-ICP-MS) methods is constrained by the characteristics of the instrumentation. The commercial availability of fast data acquisition quadrupole instruments, which allow the use of dwell times in the microsecond range rather than being restricted to milliseconds, was expected to improve the performance of the technique. When data acquisition frequency is increased, individual particles are recorded as transient signals consisting of multiple-reading events instead of one-reading pulses. Since particle events must be detected above the baseline noise, the highest intensity reading of a transient signal becomes a relevant parameter whose value decreases with decreasing dwell time, as the total intensity of a particle event is independent of the number of readings per event and thus of the selected dwell time. In this work, the effect of dwell time on the attainable size detection limits has been reconsidered, achieving minimum size detection limits when dwell times in the range of 200<em>–</em>500 μs were used, regardless of the baseline level. At such dwell times, particle events from small nanoparticles (e.g., 2<em>–</em>3 times the size detection limit) were recorded within 1<em>–</em>2 readings despite the duration of particle events, which was modified working in both standard and gas reaction modes. Under these conditions, free and proprietary software capable of handling multiple-reading events allowed to process successfully the SP-ICP-MS data independently of the dwell time applied.</div></div>","PeriodicalId":21890,"journal":{"name":"Spectrochimica Acta Part B: Atomic Spectroscopy","volume":"236 ","pages":"Article 107307"},"PeriodicalIF":3.8,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145814361","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-02-01Epub Date: 2025-12-24DOI: 10.1016/j.sab.2025.107339
George C.-Y. Chan , Gary M. Hieftje
A search for causes of intermittent mid-term (about two hours) instability in emission signals from an inductively coupled plasma led to adoption of a tandem spray-chamber arrangement and subsequently to use of a surfactant (Triton X-100) to mitigate the remaining and newly found instabilities. Through a series of investigations, abrupt signal excursions in the tandem setup were traced to droplet coagulation and drainage inside the glass tube that connected the two spray chambers. However, the signal shifts were not the result of sample-solution release directly but rather to the influence of the underlying factors on plasma behavior. Experiments tailored to the study included not only examination of temporal signal behavior but also collection of long-term videos and measurement of radiofrequency characteristics of the plasma. The addition of a surfactant, Triton X-100, for signal-stability improvement is applicable not only to systems that employ tandem spray chambers but also to conventional single Scott-type chamber arrangements. Further, use of the surfactant was unsuccessful in overcoming “acid effects”, either of the steady-state or transient nature, and did not alter plasma background or analyte signals significantly.
{"title":"Improved signal stability in inductively coupled plasma–atomic emission spectrometry through use of tandem spray chambers and surfactant addition","authors":"George C.-Y. Chan , Gary M. Hieftje","doi":"10.1016/j.sab.2025.107339","DOIUrl":"10.1016/j.sab.2025.107339","url":null,"abstract":"<div><div>A search for causes of intermittent mid-term (about two hours) instability in emission signals from an inductively coupled plasma led to adoption of a tandem spray-chamber arrangement and subsequently to use of a surfactant (Triton X-100) to mitigate the remaining and newly found instabilities. Through a series of investigations, abrupt signal excursions in the tandem setup were traced to droplet coagulation and drainage inside the glass tube that connected the two spray chambers. However, the signal shifts were not the result of sample-solution release directly but rather to the influence of the underlying factors on plasma behavior. Experiments tailored to the study included not only examination of temporal signal behavior but also collection of long-term videos and measurement of radiofrequency characteristics of the plasma. The addition of a surfactant, Triton X-100, for signal-stability improvement is applicable not only to systems that employ tandem spray chambers but also to conventional single Scott-type chamber arrangements. Further, use of the surfactant was unsuccessful in overcoming “acid effects”, either of the steady-state or transient nature, and did not alter plasma background or analyte signals significantly.</div></div>","PeriodicalId":21890,"journal":{"name":"Spectrochimica Acta Part B: Atomic Spectroscopy","volume":"236 ","pages":"Article 107339"},"PeriodicalIF":3.8,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145814367","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-01Epub Date: 2025-11-12DOI: 10.1016/j.sab.2025.107389
Ludmila Čechová , Daniel Holub , Michal Kurka , Miloslav Pouzar , Pavel Pořízka , Jozef Kaiser
Laser-induced Breakdown Spectroscopy (LIBS) is an increasingly popular method for elemental bioimaging, primarily due to its fast and multi-elemental analysis. However, achieving quantitative accuracy is highly challenging, mainly due to the strong matrix effect present in biological matrices and the lack of spatially adaptive calibration strategies. When using the conventional pixel-to-pixel calibration approach, it typically assumes a uniform sample matrix, which leads to high quantification errors when applied to biological and plant tissues. Therefore, there is a need for novel calibration methods based on a delocalized approach that take matrix variability into consideration when dealing with biological samples. This study introduces a novel delocalized approach for quantitative bioimaging of elements, particularly cadmium (Cd) and calcium (Ca), in plant tissue. A controlled sample set of Cannabis sativa plants contaminated with three different Cd concentrations was analysed at matching spatial resolution using micro-X-ray fluorescence (micro-XRF) and LIBS. A conventional pixel-to-pixel calibration was initially employed as a baseline strategy but yielded high mean absolute percentage errors (MAPE) exceeding 40 % for Cd. Therefore, a delocalised approach was developed to overcome these limitations, leveraging clustering algorithms to construct a matrix-based calibration model. This method significantly improved quantification accuracy, reducing MAPE for Cd to as low as 8.7 %, while Ca quantification achieved a score of 1.1 % MAPE. The model also exhibited minimal bias, with errors in the parts-per-million range. These results demonstrate that advanced feature selection and clustering-based calibration enable accurate quantification in highly heterogeneous plant matrices. The proposed delocalized approach demonstrates a significant advance in LIBS imaging methodology by addressing a key limitation in pixel-to-pixel calibration and may be applicable to a broader range of elements in other biological and heterogeneous systems.
{"title":"Quantitative LIBS imaging of cadmium in plant tissues with matrix-based calibration supported by micro-X-ray fluorescence spectroscopy","authors":"Ludmila Čechová , Daniel Holub , Michal Kurka , Miloslav Pouzar , Pavel Pořízka , Jozef Kaiser","doi":"10.1016/j.sab.2025.107389","DOIUrl":"10.1016/j.sab.2025.107389","url":null,"abstract":"<div><div>Laser-induced Breakdown Spectroscopy (LIBS) is an increasingly popular method for elemental bioimaging, primarily due to its fast and multi-elemental analysis. However, achieving quantitative accuracy is highly challenging, mainly due to the strong matrix effect present in biological matrices and the lack of spatially adaptive calibration strategies. When using the conventional pixel-to-pixel calibration approach, it typically assumes a uniform sample matrix, which leads to high quantification errors when applied to biological and plant tissues. Therefore, there is a need for novel calibration methods based on a delocalized approach that take matrix variability into consideration when dealing with biological samples. This study introduces a novel delocalized approach for quantitative bioimaging of elements, particularly cadmium (Cd) and calcium (Ca), in plant tissue. A controlled sample set of <em>Cannabis sativa</em> plants contaminated with three different Cd concentrations was analysed at matching spatial resolution using micro-X-ray fluorescence (micro-XRF) and LIBS. A conventional pixel-to-pixel calibration was initially employed as a baseline strategy but yielded high mean absolute percentage errors (MAPE) exceeding 40 % for Cd. Therefore, a delocalised approach was developed to overcome these limitations, leveraging clustering algorithms to construct a matrix-based calibration model. This method significantly improved quantification accuracy, reducing MAPE for Cd to as low as 8.7 %, while Ca quantification achieved a score of 1.1 % MAPE. The model also exhibited minimal bias, with errors in the parts-per-million range. These results demonstrate that advanced feature selection and clustering-based calibration enable accurate quantification in highly heterogeneous plant matrices. The proposed delocalized approach demonstrates a significant advance in LIBS imaging methodology by addressing a key limitation in pixel-to-pixel calibration and may be applicable to a broader range of elements in other biological and heterogeneous systems.</div></div>","PeriodicalId":21890,"journal":{"name":"Spectrochimica Acta Part B: Atomic Spectroscopy","volume":"235 ","pages":"Article 107389"},"PeriodicalIF":3.8,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145517469","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-01Epub Date: 2025-11-16DOI: 10.1016/j.sab.2025.107394
Shuwen Tan , Huaiqing Qin , Chengjun Li , Weizhe Ma , Xianmao Yang , Shunchun Yao
Laser Induced Breakdown Spectroscopy (LIBS) has great potential in rapid analysis of coal quality due to the unique advantages of no complex sample pretreatment, simultaneous analysis of multiple elements and fast detection. However, due to the deviation in the precision of instrumentation, there are signal intensity difference and wavelength shift in spectra collected from different instruments. As a result, the effective quantitative analysis model based on the master instrument cannot be applied to the slave instrument, which hinders the application of LIBS. Therefore, this paper proposed a method combining wavelength shift self-calibration with feature transfer learning to improve the applicability of quantitative analysis model of coal quality. The wavelength shift between master and slave instruments was corrected by the wavelength shift self-calibration method based on the standard deviation value of characteristic peak intensity. Then, the transfer learning method based on Kernel Principal Component Analysis (KPCA) and Piecewise Direct Standardization (PDS) was used to fit the spectral features between slave instrument and master instrument. Finally, the quantitative analysis model of coal quality was established by the random forest (RF). Furthermore, the Competitive Adaptive Reweighted Sampling (CARS) feature selection method was used to select the input of model. As a result, the proposed CARS-KPCA-PDS method was able to improve the adaptability of quantitative models across different LIBS Systems. Compared with the RF model without transfer learning, the mean absolute error (MAEP) of CARS-KPCA-PDS model in predicting calorific value, carbon content and ash content were reduced by 58.32 %, 71.67 % and 77.48 %. The results demonstrated that the proposed method could improve the applicability of quantitative analysis model to different instruments and reduce the modeling cost.
{"title":"Accuracy improvement of coal quality analysis across different LIBS systems by wavelength shift self-calibration and transfer learning","authors":"Shuwen Tan , Huaiqing Qin , Chengjun Li , Weizhe Ma , Xianmao Yang , Shunchun Yao","doi":"10.1016/j.sab.2025.107394","DOIUrl":"10.1016/j.sab.2025.107394","url":null,"abstract":"<div><div>Laser Induced Breakdown Spectroscopy (LIBS) has great potential in rapid analysis of coal quality due to the unique advantages of no complex sample pretreatment, simultaneous analysis of multiple elements and fast detection. However, due to the deviation in the precision of instrumentation, there are signal intensity difference and wavelength shift in spectra collected from different instruments. As a result, the effective quantitative analysis model based on the master instrument cannot be applied to the slave instrument, which hinders the application of LIBS. Therefore, this paper proposed a method combining wavelength shift self-calibration with feature transfer learning to improve the applicability of quantitative analysis model of coal quality. The wavelength shift between master and slave instruments was corrected by the wavelength shift self-calibration method based on the standard deviation value of characteristic peak intensity. Then, the transfer learning method based on Kernel Principal Component Analysis (KPCA) and Piecewise Direct Standardization (PDS) was used to fit the spectral features between slave instrument and master instrument. Finally, the quantitative analysis model of coal quality was established by the random forest (RF). Furthermore, the Competitive Adaptive Reweighted Sampling (CARS) feature selection method was used to select the input of model. As a result, the proposed CARS-KPCA-PDS method was able to improve the adaptability of quantitative models across different LIBS Systems. Compared with the RF model without transfer learning, the mean absolute error (MAE<sub>P</sub>) of CARS-KPCA-PDS model in predicting calorific value, carbon content and ash content were reduced by 58.32 %, 71.67 % and 77.48 %. The results demonstrated that the proposed method could improve the applicability of quantitative analysis model to different instruments and reduce the modeling cost.</div></div>","PeriodicalId":21890,"journal":{"name":"Spectrochimica Acta Part B: Atomic Spectroscopy","volume":"235 ","pages":"Article 107394"},"PeriodicalIF":3.8,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145569215","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-01Epub Date: 2025-10-10DOI: 10.1016/j.sab.2025.107348
Yue Zhang, Xiufang Chen, Xintong Liu, Xiangang Xu, Zhenkai Sun
With the development and application of the third generation of semiconductor materials, impurity analysis of silicon carbide (SiC) wafers has become increasingly crucial. In this study, the glow discharge mass spectrometer (GDMS) was systematically employed to establish the optimal discharge conditions for SiC wafers at 2.5 mA and 1100 V. The relative sensitivity factor (RSF) of aluminum (Al) element was determined and corrected by constructing a calibration curve. The calibration results demonstrated that the RSF value of 1.55 significantly improved the detection accuracy when the Al content ranged from 5 × 1016 cm−3 to 5 × 1017 cm−3. A comprehensive comparative analysis was conducted on wafers subjected to different processing techniques, including wire cutting, grinding, mechanical polishing (MP), and chemical mechanical polishing (CMP). The results demonstrated that wire-cut wafers exhibited markedly elevated surface elemental concentrations compared to other samples. CMP was found to be more effective in reducing the influence of surface impurities on GDMS test results. These results provide valuable insights for optimizing wafer preparation protocols to achieve more accurate impurity characterization in SiC materials.
{"title":"Study on the detection of element content of silicon carbide wafers on different processed surfaces by glow discharge mass spectrometry","authors":"Yue Zhang, Xiufang Chen, Xintong Liu, Xiangang Xu, Zhenkai Sun","doi":"10.1016/j.sab.2025.107348","DOIUrl":"10.1016/j.sab.2025.107348","url":null,"abstract":"<div><div>With the development and application of the third generation of semiconductor materials, impurity analysis of silicon carbide (SiC) wafers has become increasingly crucial. In this study, the glow discharge mass spectrometer (GDMS) was systematically employed to establish the optimal discharge conditions for SiC wafers at 2.5 mA and 1100 V. The relative sensitivity factor (RSF) of aluminum (Al) element was determined and corrected by constructing a calibration curve. The calibration results demonstrated that the RSF value of 1.55 significantly improved the detection accuracy when the Al content ranged from 5 × 10<sup>16</sup> cm<sup>−3</sup> to 5 × 10<sup>17</sup> cm<sup>−3</sup>. A comprehensive comparative analysis was conducted on wafers subjected to different processing techniques, including wire cutting, grinding, mechanical polishing (MP), and chemical mechanical polishing (CMP). The results demonstrated that wire-cut wafers exhibited markedly elevated surface elemental concentrations compared to other samples. CMP was found to be more effective in reducing the influence of surface impurities on GDMS test results. These results provide valuable insights for optimizing wafer preparation protocols to achieve more accurate impurity characterization in SiC materials.</div></div>","PeriodicalId":21890,"journal":{"name":"Spectrochimica Acta Part B: Atomic Spectroscopy","volume":"235 ","pages":"Article 107348"},"PeriodicalIF":3.8,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145364504","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-01Epub Date: 2025-10-10DOI: 10.1016/j.sab.2025.107350
Sergey M. Zaytsev, Vera A. Terashkevich
A non-local thermodynamic equilibrium (non-LTE) radiative transfer algorithm, accounting for self-absorption effect explicitly, was implemented for the simulation of high-temperature (T∼4500-6600 K) moderate resolution (Δλ ∼ 0.04 nm) spectra of the diagonal (Δυ=0) bands of B2Σ+ – X2Σ+ (violet) system of the CN radical. The experimental spectra were obtained in laser-induced plasma during the ablation of nitrogen containing carbonaceous solid target in air and emission registration at 12 different delays (0.2-6 μs) after nanosecond laser pulse. A performance comparison of the two publicly available line lists containing spectroscopic data on CN transitions in ExoMol format, namely, Trihybrid and KTPSYT, showed the advantage of the last one for experimental data fitting. Using the KTPSYT line list, a step-by-step expansion of the model was carried out, starting with the single-temperature (T) LTE and optically thin plasma and finishing with the multi-temperature (Tel = T (obtained under LTE condition), Tvib, Trot) non-LTE optically thick plasma approximations. The multi-temperature Boltzmann distribution of internal kinds of molecular motion was assumed during the non-LTE modeling. The LTE model with self-absorption was applicable for the data explanation obtained at early delays after laser pulse. Both of non-LTE and self-absorption effects appeared at the middle delays and its simultaneous consideration substantially improved the overall fit of the experimental data (the relative squared deviation of the normalized intensity decreased twice down to ∼7 % in comparison with implementation of the simple LTE model without self-absorption). At the late delays the plasma density decreases and the degree of absorption becomes low, whereas the strong difference up to 1800 K is observed between Tvib and Trot values. The significance of the adjusted plasma parameters was elucidated by routinely errors assessment.
{"title":"Accurate simulation of the CN emission spectra in laser-induced plasma: a joint impact of robust line list, non-LTE conditions and self-absorption effect","authors":"Sergey M. Zaytsev, Vera A. Terashkevich","doi":"10.1016/j.sab.2025.107350","DOIUrl":"10.1016/j.sab.2025.107350","url":null,"abstract":"<div><div>A non-local thermodynamic equilibrium (non-LTE) radiative transfer algorithm, accounting for self-absorption effect explicitly, was implemented for the simulation of high-temperature (<em>T</em>∼4500-6600 K) moderate resolution (Δ<em>λ</em> ∼ 0.04 nm) spectra of the diagonal (Δ<em>υ</em>=0) bands of <em>B</em> <sup>2</sup>Σ<sup>+</sup> – <em>X</em> <sup>2</sup>Σ<sup>+</sup> (violet) system of the CN radical. The experimental spectra were obtained in laser-induced plasma during the ablation of nitrogen containing carbonaceous solid target in air and emission registration at 12 different delays (0.2-6 μs) after nanosecond laser pulse. A performance comparison of the two publicly available line lists containing spectroscopic data on CN transitions in ExoMol format, namely, Trihybrid and KTPSYT, showed the advantage of the last one for experimental data fitting. Using the KTPSYT line list, a step-by-step expansion of the model was carried out, starting with the single-temperature (<em>T</em>) LTE and optically thin plasma and finishing with the multi-temperature (<em>T</em><sub><em>el</em></sub> = <em>T</em> (obtained under LTE condition), <em>T</em><sub><em>vib</em></sub>, <em>T</em><sub><em>rot</em></sub>) non-LTE optically thick plasma approximations. The multi-temperature Boltzmann distribution of internal kinds of molecular motion was assumed during the non-LTE modeling. The LTE model with self-absorption was applicable for the data explanation obtained at early delays after laser pulse. Both of non-LTE and self-absorption effects appeared at the middle delays and its simultaneous consideration substantially improved the overall fit of the experimental data (the relative squared deviation of the normalized intensity decreased twice down to ∼7 % in comparison with implementation of the simple LTE model without self-absorption). At the late delays the plasma density decreases and the degree of absorption becomes low, whereas the strong difference up to 1800 K is observed between <em>T</em><sub><em>vib</em></sub> and <em>T</em><sub><em>rot</em></sub> values. The significance of the adjusted plasma parameters was elucidated by routinely errors assessment.</div></div>","PeriodicalId":21890,"journal":{"name":"Spectrochimica Acta Part B: Atomic Spectroscopy","volume":"235 ","pages":"Article 107350"},"PeriodicalIF":3.8,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145326253","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Germanium is a technologically critical element with increasing environmental concerns. However, data on its potential toxic effects on the environment are limited because of the challenges associated with analyzing Ge. Determining sub-nanogram to nanogram per liter levels of Ge in natural water using ICP-MS/MS remains challenging because of low concentrations and spectral interferences. This study presents a reliable method for direct Ge determination in natural waters using ICP-MS/MS. Ge was measured at a mass-to-charge ratio (m/z) = 88 instead of 72 using N2O as the reaction gas. The reaction of 72Ge+ with N2O forms 72Ge16O+ (m/z = 88), adding 16 amu and avoiding on-mass interference at m/z = 72. Signal intensity of 72Ge16O+ improved 2.5-fold upon adding 3 % methanol, with minimal changes in background signal at m/z 88. A 13.4 % suppression of the Ge-related signal due to the matrix (100 mg L−1 NaCl and 50 mg L−1 Ca) was corrected using 103Rh as the internal standard. Under the optimized conditions, the limit of quantification was 0.10 ng L−1, with reproducibility <2 %. Results for Ge in the river-certified reference materials SLRS-5 and SLRS-6 matched reported values, confirming the reliability of the proposed method for detecting ultra-trace levels of Ge in natural waters.
{"title":"Determining germanium in natural waters by ICP-MS/MS using N2O as reaction gas and methanol as signal enhancer","authors":"Jiang-yi Zhang , Wen-jing Liu , Guang-liang Wu , Zhi-fang Xu","doi":"10.1016/j.sab.2025.107354","DOIUrl":"10.1016/j.sab.2025.107354","url":null,"abstract":"<div><div>Germanium is a technologically critical element with increasing environmental concerns. However, data on its potential toxic effects on the environment are limited because of the challenges associated with analyzing Ge. Determining sub-nanogram to nanogram per liter levels of Ge in natural water using ICP-MS/MS remains challenging because of low concentrations and spectral interferences. This study presents a reliable method for direct Ge determination in natural waters using ICP-MS/MS. Ge was measured at a mass-to-charge ratio (<em>m</em>/<em>z</em>) = 88 instead of 72 using N<sub>2</sub>O as the reaction gas. The reaction of <sup>72</sup>Ge<sup>+</sup> with N<sub>2</sub>O forms <sup>72</sup>Ge<sup>16</sup>O<sup>+</sup> (<em>m</em>/<em>z</em> = 88), adding 16 amu and avoiding on-mass interference at m/z = 72. Signal intensity of <sup>72</sup>Ge<sup>16</sup>O<sup>+</sup> improved 2.5-fold upon adding 3 % methanol, with minimal changes in background signal at <em>m</em>/<em>z</em> 88. A 13.4 % suppression of the Ge-related signal due to the matrix (100 mg L<sup>−1</sup> NaCl and 50 mg L<sup>−1</sup> Ca) was corrected using <sup>103</sup>Rh as the internal standard. Under the optimized conditions, the limit of quantification was 0.10 ng L<sup>−1</sup>, with reproducibility <2 %. Results for Ge in the river-certified reference materials SLRS-5 and SLRS-6 matched reported values, confirming the reliability of the proposed method for detecting ultra-trace levels of Ge in natural waters.</div></div>","PeriodicalId":21890,"journal":{"name":"Spectrochimica Acta Part B: Atomic Spectroscopy","volume":"235 ","pages":"Article 107354"},"PeriodicalIF":3.8,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145326251","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-01Epub Date: 2025-10-08DOI: 10.1016/j.sab.2025.107355
Zihan Yang , Shumao Bi , Yang Pu , Chun Lou , Yindi Zhang
In-situ detection of gaseous alkali metal sodium (Na) release during combustion is crucial for optimizing fuel utilization and improving operational efficiency. Combustion inherently produces emission spectra, which contain characteristic information about Na release within the flame. However, gas-phase Na in flue gas doesn't have a spontaneous emission spectrum. Laser-induced breakdown spectroscopy (LIBS) can effectively excite and detect the spectral signature of gaseous Na in flue gas. In this study, flame emission spectroscopy (FES) and LIBS were employed simultaneously to analyze Na release dynamics in flame and flue gas during the combustion of high-alkali coal. The synchronous detection of sodium release in both regions indicated a rapid migration of gas-phase Na from the flame to the flue gas. Gas-phase Na concentration in the flue gas was lower in the flue gas than in the flame, suggesting that not all sodium released in the flame migrates to the flue gas pathway. The addition of Kaolin significantly suppressed the release of Na in flame and flue gas, as well as Na migration from flame to flue gas. Furthermore, 40–50 % of Na released from the flame migrated to the flue gas under different blending conditions. This study presents a novel approach for online detection of alkali metal release during coal combustion and provides new insights for predicting slagging and fouling in coal-fired utility plants.
{"title":"Simultaneous analysis alkali metal elements using LIBS and flame emission spectroscopy: Na release during coal combustion","authors":"Zihan Yang , Shumao Bi , Yang Pu , Chun Lou , Yindi Zhang","doi":"10.1016/j.sab.2025.107355","DOIUrl":"10.1016/j.sab.2025.107355","url":null,"abstract":"<div><div>In-situ detection of gaseous alkali metal sodium (Na) release during combustion is crucial for optimizing fuel utilization and improving operational efficiency. Combustion inherently produces emission spectra, which contain characteristic information about Na release within the flame. However, gas-phase Na in flue gas doesn't have a spontaneous emission spectrum. Laser-induced breakdown spectroscopy (LIBS) can effectively excite and detect the spectral signature of gaseous Na in flue gas. In this study, flame emission spectroscopy (FES) and LIBS were employed simultaneously to analyze Na release dynamics in flame and flue gas during the combustion of high-alkali coal. The synchronous detection of sodium release in both regions indicated a rapid migration of gas-phase Na from the flame to the flue gas. Gas-phase Na concentration in the flue gas was lower in the flue gas than in the flame, suggesting that not all sodium released in the flame migrates to the flue gas pathway. The addition of Kaolin significantly suppressed the release of Na in flame and flue gas, as well as Na migration from flame to flue gas. Furthermore, 40–50 % of Na released from the flame migrated to the flue gas under different blending conditions. This study presents a novel approach for online detection of alkali metal release during coal combustion and provides new insights for predicting slagging and fouling in coal-fired utility plants.</div></div>","PeriodicalId":21890,"journal":{"name":"Spectrochimica Acta Part B: Atomic Spectroscopy","volume":"235 ","pages":"Article 107355"},"PeriodicalIF":3.8,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145326247","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
扫码关注我们
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号