Applied Spectroscopy最新文献

{"title":"EXPRESS: A Divide-and-conquer Approach that Guides Undergraduate Students in the Interpretation of Organic Infrared Spectra.","authors":"Shaun D Black","doi":"10.1177/00037028261474246","DOIUrl":"https://doi.org/10.1177/00037028261474246","url":null,"abstract":"<p><p>A divide-and-conquer approach is presented that helps undergraduate students interpret organic infrared-spectra. In this method, <i>DivnConqIR</i>, students deal with the confusion of a complicated spectrum by focusing first on the carbonyl band at ∼1720 cm^-1 near the middle of the spectrum. When present, its position and related bands can be analyzed to determine the specific functional group to which the carbonyl belongs; in its absence, students eliminate many functional groups. In either case, students begin spectral interpretation with significant accomplishment. This strategy divides the spectrum again, now at 3000 cm^-1, to define the backbone of the organic molecule and determine the possible presence of alkenes, alcohols, amines, or terminal alkynes. Students divide the spectrum again, now at 1375 cm^-1, to confirm the presence of methyl group(s) with the methyl umbrella band or, if present, isopropyl or <i>tert</i>-butyl doublet bands for further connectivity. Students divide the spectrum again, now at 1000 cm^-1, to search for the presence of one or more C-O stretches and to confirm the presence of alcohols, carboxylic acids, esters, or anhydrides, or to discover ethers. Lastly, students use <i>DivnConqIR</i> to examine unaccounted bands to identify other useful functional groups that may be present. Students interpret IR spectra without confusion and determine functional groups effectively; they integrate functional groups into possible complete structures. Qualitative and quantitative student performance data are offered to suggest the effectiveness of this interpretive approach, and <i>DivnConqIR</i> is compared to other IR interpretation methods to show that it is unique and most comprehensive. Many worked examples are presented, and additional resources are provided.</p>","PeriodicalId":8253,"journal":{"name":"Applied Spectroscopy","volume":" ","pages":"37028261474246"},"PeriodicalIF":2.2,"publicationDate":"2026-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148560687","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}

{"title":"EXPRESS: Two-dimensional Correlation Spectroscopy Studies of Infrared, Raman, and Near-infrared Spectra of Water.","authors":"Harumi Sato, Daitaro Ishikawa, Mika Ishigaki, Anqi He, Yizhunag Xu, Yukihiro Ozaki","doi":"10.1177/00037028261474225","DOIUrl":"https://doi.org/10.1177/00037028261474225","url":null,"abstract":"<p><p>This review is concerned with our recent four papers on vibrational spectroscopy studies of water. The four papers had dual purposes. One was to deepen the understanding of IR, Raman and NIR spectra of water including the low-frequency regions of IR (far-infrared; FIR) and Raman spectra, and another was to explore the structure of water and water hydrogen-bonding networks. In this review we put emphasis on the former. Particularly, the importance of 2D-COS in the spectral analysis was explained in detail. In the studies of low-frequency region of IR spectra, 2D-COS revealed that there are two or three bands assignable to libration L2 modes of tetrahedron structure (THS) and pseudo-tetrahedron structure (PTHS). Bast on these observations we concluded that there are two or three water hydrogen bonding networks with THS or PTHS species. In the NIR study of water 2D-COS was used to construct the relations between PTHS and THS bands in the NIR spectra an those in the IR spectra. 2D-COS was also useful to determine the sequence order of the events occurring during temperature increase.</p>","PeriodicalId":8253,"journal":{"name":"Applied Spectroscopy","volume":" ","pages":"37028261474225"},"PeriodicalIF":2.2,"publicationDate":"2026-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148560660","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}

{"title":"EXPRESS: Age estimation of bloodstains based on Kernel Extreme Learning Machine algorithm and Near-infrared spectroscopy technology.","authors":"Ying Liang, Qifu Yang, Jiaquan Wu, Kun Ma, Huihui Ren, Hanyu Zhu, Xingshuai Peng, Jiateng Wang, Hanyu Zhu","doi":"10.1177/00037028261474238","DOIUrl":"https://doi.org/10.1177/00037028261474238","url":null,"abstract":"<p><p>Bloodstains are among the most common forms of evidence at crime scenes and are considered one of the most critical types of physical evidence in forensic science. Accurately determining the age of bloodstains at a crime scene is crucial to solving cases. Traditionally, this determination relied on the expertise of forensic investigators or biochemical analysis methods, both of which often damaged the samples and increased investigation costs. This necessitated the development of a rapid, non-destructive, and accurate method for bloodstain age estimation. In the proposed method, bloodstains are applied to various substrates to minimize the influence of background interference on the experimental results. Spectral data are extracted non-destructively from the bloodstains and integrated with machine learning techniques to develop predictive models.The training model of blood aging was built using the Kernel Extreme Learning Machine (KELM) algorithm and the near-infrared (NIR) spectral data. It was also compared with the traditional Partial Least Squares Regression (PLS-R), Random Forest (RF) models and Back-propagation neural network (BP) models. The experimental results showed that the performance of KELM model was the best, test set with a determination coefficient (R²) of 0.94, which is higher compared to that of the PLS-R model (R² = 0.75), RF model (R² = 0.82) and BP model (R² = 0.90). Besides, the root mean square error of prediction (RMSEP) of the KELM model was 2.54 days, smaller than the PLS-R model (RMSEP = 5.18 days) , the RF model (RMSEP = 4.29days) and the BP model (RMSEP = 3.68 days).The mean absolute percentage error (MAPE) of the validation set was 2.45% when using the KELM algorithm, which was also the minimum of the three algorithms, and it represented that the prediction results were the best. The experimental data showed that the method proposed in this study could accurately estimate the age of bloodstains, providing a new technology reference for bloodstain detection.</p>","PeriodicalId":8253,"journal":{"name":"Applied Spectroscopy","volume":" ","pages":"37028261474238"},"PeriodicalIF":2.2,"publicationDate":"2026-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148560634","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}

{"title":"EXPRESS: Incidence-side-dependent terahertz refractive index response of opal-chlorite bilayer composites.","authors":"Xueqing Dai, Yanying Zhao, Yixing Geng, Zhiyuan Zheng, Chengxun Li, Chengxun Li, Haochong Huang, Shanshan Li, Kunfeng Qiu, Hao Liu","doi":"10.1177/00037028261474250","DOIUrl":"https://doi.org/10.1177/00037028261474250","url":null,"abstract":"<p><p>Layered mineral composites may exhibit incidence-side-dependent terahertz responses because interfacial reflection and unequal optical paths modify wave propagation through the structure. In this study, terahertz time-domain spectroscopy (THz-TDS) was employed to investigate the effective refractive index response of opal-chlorite bilayer composites. The results show that the refractive index difference between opposite incidence sides decreases and gradually approaches a stable level with increasing chlorite thickness. TMM inversion retrieved the chlorite refractive index spectrum in good agreement with the directly measured result. Proton irradiation applied from the opal side enhanced the asymmetry mainly in the thinnest sample, whereas this effect was rapidly suppressed as the chlorite thickness increased. In addition, the measurements under the investigated environmental conditions showed that the refractive index difference remained comparatively stable. These results provide an experimental basis for analyzing incidence-side-dependent terahertz responses in layered mineral bilayers.</p>","PeriodicalId":8253,"journal":{"name":"Applied Spectroscopy","volume":" ","pages":"37028261474250"},"PeriodicalIF":2.2,"publicationDate":"2026-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148560663","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}

{"title":"EXPRESS: Attention-based Multi-level Fusion for NIRS Modeling.","authors":"Hongyu Wang, Xiaoli Luan, Fei Liu","doi":"10.1177/00037028261474232","DOIUrl":"https://doi.org/10.1177/00037028261474232","url":null,"abstract":"<p><p>Near-Infrared Spectroscopy (NIRS) can directly provide product quality information at the molecular level, such as concentration, viscosity, etc. However, NIRS is overly sensitive to environmental noise. Therefore, how to make full use of the information of process variables to enhance the robustness of NIR modeling is the key. For this purpose, this paper presents a multi-level fusion model based on Attention Mechanism (AM). First, two-branch Convolutional Neural Network (CNN) is introduced to extract the feature of NIRS. Then, a fusion block based on AM is designed, which consists a cross-attention operation, a residual connection, and a Multi-layer Perceptron (MLP). The residual connection weights and integrates features of NIRS and process variables according to the cross-attention distribution, while the MLP further combines the features in the feature dimension. Additionally, considering different information exchanged ways of fused features at each level of two-stream CNN, two different fusion schemes are designed namely central and shared strategies. Experiments on the 2,6-dimethylphenol distillation process datasets demonstrate that proposed method outperforms some existing methods.</p>","PeriodicalId":8253,"journal":{"name":"Applied Spectroscopy","volume":" ","pages":"37028261474232"},"PeriodicalIF":2.2,"publicationDate":"2026-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148560681","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}

{"title":"A Comparison of ICP-OES and ICP-MS for Trace Impurity Analysis in High-Purity Copper ALD Precursors.","authors":"Victoria Volchek, Mikhail Zhezhera, Igor Ilyin, Andrey Ildyakov, Roland Raldugin, Askar Rezvanov, Evgeniia Vikulova","doi":"10.1177/00037028261471556","DOIUrl":"10.1177/00037028261471556","url":null,"abstract":"<p><p>Advanced ALD (atomic layer deposition) precursors are designed to deposit thin films that must be reliable, clean and free of contaminants. This created a need for analytical methods to measure contaminants and ensure the purity of the starting compounds used in ALD. However, accurate analysis of multiple trace impurity elements in high purity copper precursors is extremely challenging. The paper presents a comparison of analytical performances of the inductively coupled plasma optical emission spectrometry (ICP-OES) and the inductively coupled plasma mass spectrometry (ICP-MS) for the trace analysis of copper(II) acetylacetonate. A detailed study of the copper matrix effect and its influence on the intensity of the analytical signals was performed. The limits of detection for ICP-OES and ICP-MS analysis ranged from 0.1 to 100 ng g^-1 for more than 60 trace elements. The capabilities of the ICP-MS technique were expanded by the use of a reaction/collision cell. The combination of the developed ICP-OES and ICP-MS methods allows monitoring 62 impurities in copper(II) acetylacetonate with a purity of 6N (99.9999 wt%). The accuracy was rigorously validated through spike recovery experiments and the analysis of a high-purity copper certified reference materials, demonstrating the absence of significant systematic errors. The methodology's applicability was further confirmed by analyzing additional copper precursors, showcasing its utility for quality control of copper ALD materials.</p>","PeriodicalId":8253,"journal":{"name":"Applied Spectroscopy","volume":" ","pages":"37028261471556"},"PeriodicalIF":2.2,"publicationDate":"2026-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148535015","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}

{"title":"On-Line Monitoring of Solvent Extraction Streams by Laser-Induced Breakdown and Raman Spectroscopy.","authors":"G S Budylin, V A Petrov, E A Shirshin, M A Tarazanova, G A Sharadze, E Yu Pavlyukevich, K N Dvoeglazov, A A Zherebtsov","doi":"10.1177/00037028261471554","DOIUrl":"10.1177/00037028261471554","url":null,"abstract":"<p><p>Efficient monitoring of solvent extraction processes is essential for the safe and sustainable operation of nuclear fuel reprocessing, particularly under conditions where radiolysis and solvent degradation can affect separation efficiency and phase stability. We investigate an integrated optical approach that combines Raman spectroscopy of the organic phase with laser-induced breakdown spectroscopy (LIBS) of the aqueous phase for simultaneous control of extractant composition and raffinate elemental content. Raman spectroscopy was applied to tributyl phosphate (TBP) in a hydrocarbon diluent over a range of concentrations selected to mimic changes in extractant loading and degradation. Using closely spaced bands in the 1000-1200 cm^-1 region, a simple ratiometric indicator yielded an excellent linear correlation with TBP concentration (<i>R</i>² = 0.996) and a median prediction error of about 1.0%. LIBS measurements were performed on aqueous solutions containing Zr, La, Ce and Sr as fission-product surrogates in concentration ranges representative of late extraction stages (1-40 g L^-1). Despite shot-to-shot fluctuations associated with breakdown in liquids, internal standardization to solvent oxygen lines or a major solute element provided linear calibration curves with mean absolute percentage errors of 4-8% and limits of detection on the order of a few grams per liter. The combined Raman-LIBS scheme thus offers a promising basis for a reagent-free in situ monitoring of solvent extraction operations in nuclear fuel reprocessing.</p>","PeriodicalId":8253,"journal":{"name":"Applied Spectroscopy","volume":" ","pages":"37028261471554"},"PeriodicalIF":2.2,"publicationDate":"2026-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148535027","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}

{"title":"Multi-Pathlength Mid-IR Spectroscopy of Proteins in Aqueous Solutions Using an External Cavity Quantum Cascade Laser.","authors":"Lisa Riedlsperger, Alicja Dabrowska, Iskander Gazizov, Bernhard Lendl, Georg Ramer","doi":"10.1177/00037028261471539","DOIUrl":"10.1177/00037028261471539","url":null,"abstract":"<p><p>Mid-infrared spectroscopy is a powerful technique for probing molecular structure and composition, yet its application to aqueous systems remains limited by strong solvent absorption and the dynamic range of mid-IR detectors, which restrict the usable optical pathlength. Here, we present a quantum cascade laser-based spectroscopic setup that enables simultaneous acquisition of absorption spectra measured in transmission across a continuum of optical pathlengths using a custom-made wedge-shaped flow cell and a pyroelectric detector array. This design eliminates the need for mechanical adjustments or sample dilution, allowing direct analysis of complex liquid samples. We introduce the pathlength-to-noise ratio as a novel metric for determination of the optimal pathlength region for every wavenumber. By weighing detector signals based on this ratio, we achieve robust integration of multi-pathlength data into a single coherent mid-IR absorption spectrum. The system was validated using aqueous protein solutions of bovine serum albumin and β-lactoglobulin in the range of 1 to 25 mg mL^-1. Characteristic amide I and II bands were successfully resolved, and secondary structure differences were detected. This work establishes a flexible approach to mid-IR absorption spectroscopy, aiming to eliminate the limitations of detectors with a small dynamic range and to get a better understanding of the optimal pathlength for complex samples.</p>","PeriodicalId":8253,"journal":{"name":"Applied Spectroscopy","volume":" ","pages":"37028261471539"},"PeriodicalIF":2.2,"publicationDate":"2026-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148535071","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}

{"title":"EXPRESS: A rapid and nondestructive approach for identification of foodborne bacteria using hyperspectral imaging and multimodal technology.","authors":"Xinlei Liu, Wei Li, Yibo Zhang, Zhihong Wei, Shengfeng Cui, Zehua Zhao","doi":"10.1177/00037028261474221","DOIUrl":"https://doi.org/10.1177/00037028261474221","url":null,"abstract":"<p><p>Foodborne illnesses pose a serious threat to food safety and cause substantial economic losses. Hyperspectral imaging (HSI) has emerged as a powerful tool for rapid and non-destructive identification of foodborne pathogens. However, the high chemical similarity among different pathogen categories presents a challenge for accurate discrimination. To address this issue, we developed an optimized machine learning framework integrated with HSI that incorporates multimodal learning and a multi-head attention mechanism, enabling deeper extraction and fusion of spectral profiles and intensity images features. In visualization analyses, the deeply fused features demonstrated excellent inter-species separability, and the proposed multimodal multi-head attention fusion (MMAF) strategy achieved a high identification accuracy of 96.29%, representing an improvement of 4.17% over the single-modal approach. These results indicate that the optimized HSI approach, driven by advanced machine learning, holds great potential as an effective tool for rapid detection of microbial contamination in food products.</p>","PeriodicalId":8253,"journal":{"name":"Applied Spectroscopy","volume":" ","pages":"37028261474221"},"PeriodicalIF":2.2,"publicationDate":"2026-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148535068","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}

{"title":"EXPRESS: Dye-Dependent Fluorescence Enhancement in ZnO Nanorod-Polymer Films: Excitation and Emission Contributions Probed by Time-Resolved Fluorescence.","authors":"Alexandra Falamas, Ioana Cardan, Denisa Cuibus, Maria Stefan, Cosmin Farcau","doi":"10.1177/00037028261470429","DOIUrl":"https://doi.org/10.1177/00037028261470429","url":null,"abstract":"<p><p>The interaction of light with nanostructured materials enables control over emission processes and photonic environments at the nanoscale. In this work, we investigate the dye-dependent fluorescence modulation induced by dielectric nanostructures using thin films based on ZnO nanorods (NRs). Two representative fluorophores with emission spanning the visible spectral range, Nile Blue and Coumarin 6, were embedded in polyvinylpyrrolidone (PVP) spacer layers of varying thicknesses and spin-coated onto ZnO NRs films prepared by a drop-coating protocol. Steady-state and time-resolved fluorescence spectroscopy were employed to quantify modifications in emission intensity and excited state dynamics arising from the interaction between the fluorophores and the nanostructured substrate. Both dyes exhibited pronounced fluorescence enhancement in the presence of the ZnO NRs, reaching up to ∼ 15× for Nile Blue and ∼ 9× for Coumarin 6 relative to glass substrates, dependent on the PVP layer thickness. Time-correlated single photon counting measurements revealed modest lifetime reductions upon deposition on ZnO, indicating that fluorescence enhancement is not dominated by strong radiative-rate modification or interfacial charge transfer. The results suggest that the observed emission amplification arises from a combination of excitation-field enhancement and improved emission extraction mediated by wavelength-dependent scattering from the ZnO NRs. The excitation-wavelength dependence of the enhancement is consistent with scattering-assisted redistribution of the excitation light, which may increase the effective excitation experienced by the fluorophores. Additionally, numerical aperture-dependent fluorescence measurements and polarization-resolved anisotropy investigations are consistent with scattering-assisted redistribution and extraction of emitter photons that would otherwise remain partially trapped within the PVP film by total internal reflection.</p>","PeriodicalId":8253,"journal":{"name":"Applied Spectroscopy","volume":" ","pages":"37028261470429"},"PeriodicalIF":2.2,"publicationDate":"2026-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148395526","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}