Applied Spectroscopy最新文献_第3页

Simple Estimation of Errors and Multi-Pixel Signal-to-Noise Ratio for Gaussian, Lorentzian, and Pseudo-Voigt functions Fit to Noisy Spectral Data. 高斯，洛伦兹和伪voigt函数适合噪声光谱数据的误差和多像素信噪比的简单估计。

IF 2.2 3区化学

Applied Spectroscopy Pub Date : 2026-08-01 Epub Date: 2026-05-21 DOI: 10.1177/00037028261446995

Ryan S Jakubek, Rohit Bhartia, Marc D Fries

{"title":"Simple Estimation of Errors and Multi-Pixel Signal-to-Noise Ratio for Gaussian, Lorentzian, and Pseudo-Voigt functions Fit to Noisy Spectral Data.","authors":"Ryan S Jakubek, Rohit Bhartia, Marc D Fries","doi":"10.1177/00037028261446995","DOIUrl":"10.1177/00037028261446995","url":null,"abstract":"Quantification of band parameters in spectral data typically requires iteratively fitting the spectroscopic feature to Gaussian, Lorentzian, or pseudo-Voigt functions for the extraction of band height, width, position, and area values. However, there are currently no adequate methods of measuring their errors. Previously, Lenz and Ayres [\"Errors Associated with Fitting Gaussian Profiles to Noisy Emission-Line Spectra\". Publications of the Astronomical Society of the Pacific. 1992. 104: 1104. DOI: 10.1086/133096] addressed this problem for Gaussian fits by empirically fitting a set of model data to derive equations for the calculation of Gaussian band parameter errors. However, the treatment of only Gaussian fitting functions greatly limits utility. In this study, we extend their error calculation methods to include Lorentzian and pseudo-Voigt fits for error analysis in a wide range analytical techniques that utilize spectral fitting. We do this empirically by fitting a model dataset of noisy spectral signals to Gaussian, Lorentzian, and pseudo-Voigt functions to calculate the accuracy and precision of the fits. We derive a set of equations for the simple calculation of band fitting errors. In addition, the simple calculation of band height and area errors allows for easy calculation of multi-pixel signal-to-noise ratios that were previously shown to significantly improve instrument limit-of-detection [Jakubek et al. \"Improving Spectroscopic Detection Limits with Multi-Pixel Signal-to-Noise Ratio Calculations: Application to the SHERLOC Instrument Aboard the Perseverance Rover\". Analytica Chimica Acta. 2025. 1357: 344072. DOI: 10.1016/j.aca.2025.344072]. The results of this work are broadly applicable to most analytical techniques that produce spectral data.","PeriodicalId":8253,"journal":{"name":"Applied Spectroscopy","volume":" ","pages":"821-836"},"PeriodicalIF":2.2,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147980221","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Anharmonic Debye-Waller Factor in the X-ray Absorption Fine Structure (XAFS) Spectroscopy of Silver: A Classical Statistical Approach. 银的x射线吸收精细结构（XAFS）光谱中的非调和德拜-沃勒因子：一种经典的统计方法。

IF 2.2 3区化学

Applied Spectroscopy Pub Date : 2026-08-01 Epub Date: 2026-07-07 DOI: 10.1177/00037028261444765

Le Duy Manh, Tong Sy Tien, Duong Vu Truong, Nguyen Huy Thao, Nguyen Van Thu, Nguyen Ba Hung

{"title":"Anharmonic Debye-Waller Factor in the X-ray Absorption Fine Structure (XAFS) Spectroscopy of Silver: A Classical Statistical Approach.","authors":"Le Duy Manh, Tong Sy Tien, Duong Vu Truong, Nguyen Huy Thao, Nguyen Van Thu, Nguyen Ba Hung","doi":"10.1177/00037028261444765","DOIUrl":"10.1177/00037028261444765","url":null,"abstract":"The anharmonic Debye-Waller (DW) factor in the X-ray absorption fine structure (XAFS) spectroscopy of crystalline silver (Ag) is explicitly examined, accounting for thermal disorder. A framework combining classical statistical mechanics with the correlated Einstein model is employed to describe atomic interactions and lattice vibrations. The DW factor characterizes attenuation of the XAFS amplitude induced by thermal motion and is essential for extracting structural and thermodynamic information from XAFS spectra. The derived thermodynamic XAFS parameters incorporate atomic correlations and anharmonicity, accounting for nearest-neighbor effects on both the absorber and backscatterer. The analytical expressions for these parameters are derived in a simple, explicit, temperature-dependent form, making them convenient for XAFS analysis. The applicability of the classical approximation is quantitatively assessed through comparison with quantum-mechanical expressions for lattice vibrations. Adopting a conservative criterion of less than 10% deviation, the classical description is reliable for temperatures T <math><mo>≳</mo></math> 148 K, and the quantitative analysis is restricted to this range. Numerical results for Ag show good agreement with predictions from the anharmonic correlated Debye model, fitting method, and experimental data within the validated temperature range.Resultsat lower temperatures illustrate the breakdown of the classical approximation and are not used for quantitative interpretation. Theoretical and experimental Fourier transform magnitudes |χ(R)| from k2 weighted spectra match closely near the first-shell peak. Overall, the present approach provides an effective framework for anharmonic XAFS DW analysis in Ag at elevated temperatures and is extendable to other metals.","PeriodicalId":8253,"journal":{"name":"Applied Spectroscopy","volume":" ","pages":"837-850"},"PeriodicalIF":2.2,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148395538","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Revealing Buried Thermal Responses in Polymer Multilayers Using Photothermal Mirror Infrared Spectroscopy. 利用光热镜红外光谱揭示聚合物多层膜的埋藏热响应。

IF 2.2 3区化学

Applied Spectroscopy Pub Date : 2026-08-01 Epub Date: 2026-05-05 DOI: 10.1177/00037028261445123

Yide Zhang, Nelson G C Astrath, Lena Neubauer, Georg Ramer, Bernhard Lendl

{"title":"Revealing Buried Thermal Responses in Polymer Multilayers Using Photothermal Mirror Infrared Spectroscopy.","authors":"Yide Zhang, Nelson G C Astrath, Lena Neubauer, Georg Ramer, Bernhard Lendl","doi":"10.1177/00037028261445123","DOIUrl":"10.1177/00037028261445123","url":null,"abstract":"Depth-resolved characterization of buried layers is crucial for understanding energy transport and optical response in multilayer materials. Photothermal signal generation in such systems is commonly viewed in terms of heat loss and signal attenuation, with amplitude and sensitivity decreasing rapidly as overlayer thickness increases. Here, we demonstrate that the photothermal mirror infrared (PTM-IR) technique exhibits the opposite behavior: its transient signal increases with overlayer thickness, driven by enhanced surface displacement resulting from improved thermal confinement within the overlayer. A combined finite-element analysis (FEA) and one-dimensional analytical model based on Green's function formalism quantitatively describe the temperature and surface displacement dynamics in multilayer materials. Experiments on poly(methyl methacrylate)-polystyrene (PMMA-PS) bilayers on CaF2 substrates validate the model, showing excellent agreement between theory and measurement. The results establish PTM-IR as a non-destructive infrared technique capable of probing buried absorbers and determining both absorber and overlayer thicknesses, extending the reach of depth-restricted photothermal techniques toward deeper, non-contact subsurface characterization.","PeriodicalId":8253,"journal":{"name":"Applied Spectroscopy","volume":" ","pages":"859-865"},"PeriodicalIF":2.2,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147832883","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

EXPRESS: Adulteration Detection for Poria Cocos Based on Near-Infrared Two-Dimensional Correlation Spectroscopy and Deep Learning. 基于近红外二维相关光谱和深度学习的茯苓掺假检测。

IF 2.2 3区化学

Applied Spectroscopy Pub Date : 2026-08-01 DOI: 10.1177/00037028261474589

Rongzhen Mao, Jing Liang, Mingyue Huang, Bin Wang, Xiaoxuan Xu, Jing Xu

{"title":"EXPRESS: Adulteration Detection for Poria Cocos Based on Near-Infrared Two-Dimensional Correlation Spectroscopy and Deep Learning.","authors":"Rongzhen Mao, Jing Liang, Mingyue Huang, Bin Wang, Xiaoxuan Xu, Jing Xu","doi":"10.1177/00037028261474589","DOIUrl":"https://doi.org/10.1177/00037028261474589","url":null,"abstract":"As a traditional Chinese medicinal material, the quality of Poria cocos (PC) significantly affects its pharmacological efficacy. However, adulteration of PC in the market has been frequently observed. Adulterated PC not only compromises its medicinal value but also poses potential risks to public health. Conventional identification methods are often labor-intensive, destructive, and insufficiently sensitive to complex adulteration scenarios. In this study, a rapid and nondestructive strategy for both qualitative and quantitative analysis of PC adulteration is developed by integrating near-infrared (NIR) two-dimensional correlation spectroscopy (2DCOS) with deep learning algorithms. NIR spectra in the range of 960-1600 nm are collected from pure PC and samples adulterated with 5 common adulterants at concentration gradients of 5%. Specifically, to enhance spectral resolution, a systematic 2DCOS dataset is established by combining 5 representative spectral preprocessing methods with 2 types of 2DCOS. Furthermore, a bidirectional long short-term memory network with an attention mechanism (BiLSTM-Attn) is proposed to fully exploit the sequential dependency of correlation features embedded in 2DCOS maps. Compared with experiments involving convolutional neural network (CNN), gated recurrent unit (GRU), long short-term memory (LSTM), and bidirectional LSTM (BiLSTM) models, the proposed BiLSTM-Attn achieved 100% classification accuracy and superior regression performance, with a mean coefficient of determination (R2) of 0.9920, a low root mean squared error (RMSE) of 2.41, and a high mean residual predictive deviation (RPD) of 12.85. Extended experiments demonstrate that the combination of NIR 2DCOS and deep learning algorithms enables accurate and robust detection of PC adulteration. The proposed framework offers valuable support for quality control in traditional Chinese medicine, and has a wide range of applications.","PeriodicalId":8253,"journal":{"name":"Applied Spectroscopy","volume":" ","pages":"37028261474589"},"PeriodicalIF":2.2,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148648320","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Silica Nanoparticle and Microwave Plasma Torch Effects on Laser-Induced Breakdown Spectroscopy. 纳米二氧化硅和微波等离子体炬对激光诱导击穿光谱的影响。

IF 2.2 3区化学

Applied Spectroscopy Pub Date : 2026-08-01 Epub Date: 2026-05-19 DOI: 10.1177/00037028261449275

Chen Yang, Zhihang Lai, Shujia Wu, Tianju Li, Shengping Liu, Liangyong Zhao, Jingfeng Xie, Youning Chen, Shaohua Sun, Zuoye Liu, Bitao Hu

{"title":"Silica Nanoparticle and Microwave Plasma Torch Effects on Laser-Induced Breakdown Spectroscopy.","authors":"Chen Yang, Zhihang Lai, Shujia Wu, Tianju Li, Shengping Liu, Liangyong Zhao, Jingfeng Xie, Youning Chen, Shaohua Sun, Zuoye Liu, Bitao Hu","doi":"10.1177/00037028261449275","DOIUrl":"10.1177/00037028261449275","url":null,"abstract":"Laser-induced breakdown spectroscopy (LIBS) is a commonly used elemental analysis technique, often combined with other methods to achieve effective detection of element concentrations in samples. In this work, we investigated the effects of silica nanoparticles and a microwave plasma torch (MPT) on the emission spectral signals of titanium (Ti) in LIBS. The laser energy was optimized, and the emission intensities at different silica nanoparticle concentrations were compared. Furthermore, the finite-difference time-domain (FDTD) method was employed to simulate variations in electric field intensity in order to verify the optimal nanoparticle concentration, and time-resolved experiments were conducted to explore the evolution of the emission spectra. The results silica nanoparticles significantly increase plasma electron density, which in turn enhances both emission intensity and signal-to-noise ratio (SNR). In addition, it demonstrates that the MPT extends the plasma lifetime, thereby enhancing the accumulated emission signal. When silica nanoparticles were combined with MPT using nanoparticle-enhanced laser-induced breakdown spectroscopy (MPT-NELIBS), it achieved substantial improvements in spectral intensity and SNR and reduce the dependence of NELIBS on nanoparticles. Ultimately, this method exhibited excellent performance in the quantitative detection of Ti, with the determination coefficient (R2) of the calibration curve increasing to 0.999 and the limit of detection (LOD) decreasing to 0.14 parts-per-million (ppm), highlighting its great potential for highly sensitive trace element analysis.","PeriodicalId":8253,"journal":{"name":"Applied Spectroscopy","volume":" ","pages":"851-858"},"PeriodicalIF":2.2,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147969940","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Wave Lensing Effects on a Remote Raman Sensor: Enhanced Mean and the Intensity Distribution of Raman Flashes. 远程拉曼传感器上的波透镜效应：拉曼闪烁的均值和强度分布的增强。

IF 2.2 3区化学

Applied Spectroscopy Pub Date : 2026-08-01 Epub Date: 2026-05-26 DOI: 10.1177/00037028261455069

Paige K Williams, Whitney E Schuler, Zechariah B Kitzhaber, Caitlyn M English, Nikolaos Vitzilaios, Tammi L Richardson, Michael L Myrick

{"title":"Wave Lensing Effects on a Remote Raman Sensor: Enhanced Mean and the Intensity Distribution of Raman Flashes.","authors":"Paige K Williams, Whitney E Schuler, Zechariah B Kitzhaber, Caitlyn M English, Nikolaos Vitzilaios, Tammi L Richardson, Michael L Myrick","doi":"10.1177/00037028261455069","DOIUrl":"10.1177/00037028261455069","url":null,"abstract":"The water OH Raman band has been used as an internal standard for remote airborne measurements of fluorescence in water, but the Raman and fluorescence signals of airborne sensors can be perturbed by surface waves that induce a focusing or diverging effect. This lensing effect of waves changes the strength and effective sampling depth of optical signals detected by a remote sensor relative to the flat-water condition. In this work, a small remote optical sensor was used to observe the impact of the lensing effect on Raman scattering of water in a diving pool. This manuscript reports the impact of avalanche multiplication noise on the Raman scattering of flat water; the appearance of bright wave-induced Raman \"flashes\" analogous to, but stronger than, those observed for sunlight focusing; an approximately logarithmic distribution of signal strengths; and an increase in the average signal strength observed in the presence of waves. A mathematical model of the lensing effect in weak lensing conditions was developed for sinusoidal waves and employed to interpret the observed variability of the Raman signal.","PeriodicalId":8253,"journal":{"name":"Applied Spectroscopy","volume":" ","pages":"866-880"},"PeriodicalIF":2.2,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148013182","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

EXPRESS: Percolation-Governed Transitions in Recycled Epoxy Composites: A Terahertz Spectroscopy Framework for Multiscale Degradation and Property Prediction. 循环环氧复合材料的渗透控制转变：多尺度降解和性能预测的太赫兹光谱框架。

IF 2.2 3区化学

Applied Spectroscopy Pub Date : 2026-08-01 DOI: 10.1177/00037028261477156

Bryan Foong Zhi Chuan, Steve Wu Qing Yang, Wang Xiaobai, Angeline Tan Yan Xuan, Cho Ching Mui, Tay Siok Wei, Jing Zhang, Ke Lin

{"title":"EXPRESS: Percolation-Governed Transitions in Recycled Epoxy Composites: A Terahertz Spectroscopy Framework for Multiscale Degradation and Property Prediction.","authors":"Bryan Foong Zhi Chuan, Steve Wu Qing Yang, Wang Xiaobai, Angeline Tan Yan Xuan, Cho Ching Mui, Tay Siok Wei, Jing Zhang, Ke Lin","doi":"10.1177/00037028261477156","DOIUrl":"https://doi.org/10.1177/00037028261477156","url":null,"abstract":"This work utilized terahertz time-domain spectroscopy (THz-TDS) and Fourier Transform Infrared (FTIR) spectroscopy to characterize epoxy blends. The epoxy blends were prepared by blending a virgin DER-332/LC-100 epoxy system with Recovered Epoxy Polymer (REP) at 1-10 wt%, and were compared with references of virgin epoxy and REP. The REP was obtained via peracetic acid digestion of Carbon Fibre Reinforced Polymer (CFRP), followed by purification. Using THz-TDS amplitude-phase analysis, five optical parameters were obtained: refractive index (n), extinction coefficient (κ), absorption coefficient (α), and the real and imaginary of the dielectric constant (ε' and ε″). Under ambient conditions, these parameters extracted from THz-TDS were unable to distinguish low REP content 0-10% REP but were able to clearly differentiate 100% REP from all other epoxy blends. Compared to the other blends, 100% REP shows markedly increased n, κ, α, ε', and ε″, attributed to oxidation, formation of polar groups, chain scission and microvoid-induced scattering. To distinguish low REP-content blends using THz-TDS, external perturbation was applied. Under perturbation, linear concentration-dependent trends in Δn, Δκ, Δα, Δε' and Δε'' were observed. The external perturbation enhanced the interaction between the samples and the THz wave, likely due to amplification of dipole relaxation. Additionally, the transmission spectra (3500-7500 cm⁻1) obtained from FTIR increased as the REP content increased from 0-10%. This concentration dependent trend can be attributed to partial network dilution and reduced overtone absorption. However, the transmission of 100% REP showed strong attenuation due to structural disorder and enhanced scattering.","PeriodicalId":8253,"journal":{"name":"Applied Spectroscopy","volume":" ","pages":"37028261477156"},"PeriodicalIF":2.2,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148648284","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

EXPRESS: Absorption and Fluorescence Properties of Tracer Dyes in Complex Nonpolar Hydrocarbon Mixtures. EXPRESS：示踪染料在复杂非极性烃混合物中的吸收和荧光特性。

IF 2.2 3区化学

Applied Spectroscopy Pub Date : 2026-07-22 DOI: 10.1177/00037028261474247

Mirko Geiger, Dieter Brüggemann

{"title":"EXPRESS: Absorption and Fluorescence Properties of Tracer Dyes in Complex Nonpolar Hydrocarbon Mixtures.","authors":"Mirko Geiger, Dieter Brüggemann","doi":"10.1177/00037028261474247","DOIUrl":"https://doi.org/10.1177/00037028261474247","url":null,"abstract":"Laser-induced Fluorescence (LIF) is widely employed in combustion research for various diagnostic applications, including the simultaneous visualisation of liquid and vapour phase as well as temperature and concentration measurements. For quantitative LIF diagnostics, liquid fuels are often doped with fluorescent tracers whose spectroscopic properties must be carefully characterised. While numerous dyes have been investigated in polar solvents like water or ethanol, data for nonpolar fluids like common combustion fuels remain scarce. However, solvent polarity is known to significantly affect solubility, their optical response, spectral shape as well as influencing shifts in absorption and emission maxima. This study provides a systematic comparison of the fluorescent dyes Coumarin 152, Fluoranthene, DCM, and Pyrromethene 567 with respect to their suitability quantitative two-colour LIF thermometry in combustion diagnostics and single-droplet evaporation experiments. Measurements are conducted in three nonpolar fuels: a fossil (B0) diesel and two synthetic alternatives, gas-to-liquid (GtL) and power-to-liquid (PtL) diesel. A systematic comparison of dye performance is presented, including solubility limits as well as temperature-dependent LIF response under 355 and 532 nm excitation. Despite its comparatively lower solubility, Pyrromethene 567 exhibits high signal intensities and a pronounced temperature-dependent response, qualifying it as suitable tracer for 2-colour LIF (2c-LIF) measurements in these fuels. The results support an informed selection of tracer-fuel combinations and contribute to improved reliability of LIF-based temperature and concentration measurements in nonpolar mixtures and real fuel application.","PeriodicalId":8253,"journal":{"name":"Applied Spectroscopy","volume":" ","pages":"37028261474247"},"PeriodicalIF":2.2,"publicationDate":"2026-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148560726","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

EXPRESS: An In-Context Learning Framework for Small-Sample Coal Ash Quantification via Laser-Induced Breakdown Spectroscopy. EXPRESS：基于激光诱导击穿光谱的小样本煤灰定量的语境学习框架。

IF 2.2 3区化学

Applied Spectroscopy Pub Date : 2026-07-22 DOI: 10.1177/00037028261474584

Bo Cheng, Zhoushuai Chen, Cunguang Lou, Yunfei Li, Ruikai Li

{"title":"EXPRESS: An In-Context Learning Framework for Small-Sample Coal Ash Quantification via Laser-Induced Breakdown Spectroscopy.","authors":"Bo Cheng, Zhoushuai Chen, Cunguang Lou, Yunfei Li, Ruikai Li","doi":"10.1177/00037028261474584","DOIUrl":"https://doi.org/10.1177/00037028261474584","url":null,"abstract":"The combination of laser-induced breakdown spectroscopy (LIBS) and machine learning provides a rapid approach for coal ash quantification. However, in practical coal preparation plants, calibration samples are often limited, and ash contents are usually confined to a narrow range, making reliable quantitative modeling difficult. To address this issue, we propose a structured spectral in-context learning framework for small-sample coal ash quantification. Unlike conventional methods that rely on task-specific iterative parameter optimization, the proposed framework performs downstream inference by conditioning on a limited set of calibration samples using a pre-trained tabular foundation model. To adapt continuous high-dimensional LIBS spectra to this framework, segmented statistical descriptors and multi-scale Haar-like features were constructed to capture subtle local spectral variations associated with narrow ash-content changes. The experimental results show that the proposed SS-ICL framework achieves robust predictive performance under restricted conditions, with an R2 of 0.8880 and an RMSE of 0.1953 in a narrow-range washed-coal scenario. These results demonstrate that the proposed framework provides a practical and robust strategy for on-site LIBS-based coal quality analysis in restricted industrial environments.","PeriodicalId":8253,"journal":{"name":"Applied Spectroscopy","volume":" ","pages":"37028261474584"},"PeriodicalIF":2.2,"publicationDate":"2026-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148560698","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

EXPRESS: Electric-Field Assisted Laser-Induced Breakdown Spectroscopy (LIBS) for the analysis of Li Ore. EXPRESS：电场辅助激光诱导击穿光谱（LIBS）分析锂矿。

IF 2.2 3区化学

Applied Spectroscopy Pub Date : 2026-07-22 DOI: 10.1177/00037028261474234

Rida Arooj, Amir Fayyaz, Haroon Asghar, Z A Umar, M A Baig, Rizwan Ahmed

{"title":"EXPRESS: Electric-Field Assisted Laser-Induced Breakdown Spectroscopy (LIBS) for the analysis of Li Ore.","authors":"Rida Arooj, Amir Fayyaz, Haroon Asghar, Z A Umar, M A Baig, Rizwan Ahmed","doi":"10.1177/00037028261474234","DOIUrl":"https://doi.org/10.1177/00037028261474234","url":null,"abstract":"The X-ray fluorescence (XRF) spectroscopy is widely used in mining for elemental analysis, but it cannot detect lithium (Li) due to its low atomic number. The low sensitivity and high detection limits of conventional laser-induced breakdown spectroscopy (LIBS) also present serious challenges for analyzing lithium ore. This work demonstrates improved analytical capabilities of LIBS by using an external electric field to detect Li and other trace elements in Li ore. A notable increase in emission intensity and detection sensitivity for all trace elements has been observed in electric field-assisted LIBS (EF-LIBS) compared to conventional LIBS. Significant changes in plasma parameters, such as stabilized electron density and an extended plasma lifespan (∼10 μs), were achieved by applying the electric field, resulting in better spectral signals. The most impressive improvement was an eightfold increase in the detection limit for lithium, which decreased from 46.07 ppm (traditional LIBS) to 5.93 ppm (EF-LIBS). Increased excitation efficiency under the electric field and a longer plasma plume lifetime are responsible for this enhancement. For lithium exploration and mining, EF-LIBS offers a better alternative to traditional methods due to its field-deployable design and low sample requirements, providing increased sensitivity and operational advantages without the need for additional complex equipment.","PeriodicalId":8253,"journal":{"name":"Applied Spectroscopy","volume":" ","pages":"37028261474234"},"PeriodicalIF":2.2,"publicationDate":"2026-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148560668","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0