Applied Spectroscopy最新文献

{"title":"Dual-Branch Multiscale Attention Network (DMANet): Integrating Dynamic Two-Dimensional Correlation Spectroscopy Using a Dual-Branch Multiscale Attention Network for Beef Adulteration.","authors":"Mingyue Huang, Hailong Feng, Jing Liang, Yu Xue, Xuan Xu, Xiaoxuan Xu, Bin Wang, Jing Xu","doi":"10.1177/00037028261438812","DOIUrl":"https://doi.org/10.1177/00037028261438812","url":null,"abstract":"<p><p>To address the detection of low-level duck meat adulteration in beef, this study proposes a method based on near-infrared (NIR) two-dimensional correlation spectroscopy (2D-COS) and a dual-branch multiscale attention network (DMANet), enabling semi-quantitative prediction of duck meat content. The approach expands one-dimensional (1D) NIR spectra into synchronous and asynchronous 2D-COS, constructing a dual-branch network that extracts complementary characteristics using multiscale convolution. An adaptive attention mechanism dynamically fuses the two spectral modalities, enhancing sensitivity to subtle adulteration traits. Experiments show the model achieves 100% overall accuracy on the test set, outperforming a traditional partial least squares (PLS) model (81.6%) and single-input models (94.6% for synchronous and 92.8% for asynchronous maps). In the 0.5-5% adulteration range, it improves accuracy by 31.3%, 12.5%, and 18.7% over these benchmarks, respectively. Notably, 2D-COS consistently surpasses 1D spectral models in detecting low-content adulteration by amplifying dynamic spectral responses and strengthening characteristics of trace contaminants.</p>","PeriodicalId":8253,"journal":{"name":"Applied Spectroscopy","volume":" ","pages":"37028261438812"},"PeriodicalIF":2.2,"publicationDate":"2026-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147832915","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":"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":"https://doi.org/10.1177/00037028261445123","url":null,"abstract":"<p><p>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.</p>","PeriodicalId":8253,"journal":{"name":"Applied Spectroscopy","volume":" ","pages":"37028261445123"},"PeriodicalIF":2.2,"publicationDate":"2026-05-05","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}

{"title":"Investigation of Gramicidin A Incorporation into Phospholipid Vesicle Bilayers Using Optical-Trapping Confocal Raman Microscopy.","authors":"Jay P Kitt, Joel M Harris","doi":"10.1177/00037028261442539","DOIUrl":"https://doi.org/10.1177/00037028261442539","url":null,"abstract":"<p><p>Pore-forming peptides are a pharmacologically relevant class of membrane-active molecules capable of self-assembling in phospholipid bilayers to form transmembrane ion channels that induce uncontrolled ion flux, disrupting cellular homeostasis. Developing mechanistic insight into how these molecules perturb lipid-bilayer structure is critical for understanding their biological activity and for rational design of next-generation antimicrobials. In this work, optical-trapping confocal Raman microscopy was employed to investigate the structural impact of gramicidin A (gA) incorporation into individual 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) phospholipid vesicle bilayers as a function of peptide concentration in the vesicle membrane. Raman spectra acquired from individual, optically trapped vesicles confirmed gA incorporation through observation of peptide-specific tryptophan vibrational markers. Concentration-dependent spectra collected from 0 to 20 mol% gA vesicles revealed systematic disordering of DMPC acyl chains, observed through changes in the C-C stretching, C-H twisting, and C-H bending regions, consistent with bilayer deformation driven by hydrophobic mismatch between the gA channel and surrounding lipid chains. Self-modeling curve resolution analysis of the concentration-dependent spectra identified two spectral components: an ordered bilayer of unperturbed DMPC chains, and a gA-perturbed disordered bilayer. The amplitude of the two components vary linearly with gA concentration but with opposite sign. This result is consistent with each additional gA channel generating a localized region of disordered boundary lipids whose population grows in proportion with peptide concentration. Lipids not within the local region perturbed by the presence of gA remain ordered and decrease in proportion to their diminishing population until they disappear when the gA concentration reaches ∼20 mol%, indicating that 7-8 lipids surrounding each gA channel are impacted by hydrophobic mismatch. These results establish optical-trapping confocal Raman microscopy as an effective method for quantitative, single-vesicle investigation of peptide-membrane interactions, and highlight the power of model-free spectral analysis for unconstrained resolution of the peptide impact on membrane structure.</p>","PeriodicalId":8253,"journal":{"name":"Applied Spectroscopy","volume":" ","pages":"37028261442539"},"PeriodicalIF":2.2,"publicationDate":"2026-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147809945","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":"Sub-Second, Sensitive and Multispecies Detection of Volatile Organic Compounds Using a Mid-Infrared Broadband Supercontinuum Source and Upconversion Spectrometer.","authors":"Yueyu Lin, Paola Formica, Roderik Krebbers, Amir Khodabakhsh, Simona M Cristescu","doi":"10.1177/00037028261446656","DOIUrl":"https://doi.org/10.1177/00037028261446656","url":null,"abstract":"<p><p>Reliable monitoring and analysis of volatile organic compounds (VOCs) are crucial for environmental monitoring and human health. In this work, we report a system for fast, sensitive, and multispecies detection of VOCs by combining a fiber-based broadband mid-infrared (MIR) supercontinuum (SC) source with an upconversion spectrometer. The system's performance in terms of species identification accuracy, robustness against inter-species interference and real-time multi-species detection capability was evaluated by monitoring and tracing the evaporation dynamics of three VOCs, i.e., acetone, ethanol, and α-pinene. We achieved detection limits of 30 parts per million per meter (ppm·m), 5 ppm·m, and 0.6 ppm·ּּm in 1 second for these three compounds, respectively. Furthermore, the evaporation behavior of individual compounds from a mixture was investigated to demonstrate the system's capability for dynamic multicomponent analysis.</p>","PeriodicalId":8253,"journal":{"name":"Applied Spectroscopy","volume":" ","pages":"37028261446656"},"PeriodicalIF":2.2,"publicationDate":"2026-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147810004","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-Reflectance-Spectroscopy, Part III: In-Line Monitoring of Milk Fat Globule Size via Sauter Diameter Using an Optical Sensor.","authors":"Sebastian Boldt, Gert Sinn, Klaus-Henrik Mittenzwey, Ouwen Zhai, Henry Mittenzwey, Dietmar Lerche, Marco Gleiß, Hermann Nirschl","doi":"10.1177/00037028261440919","DOIUrl":"https://doi.org/10.1177/00037028261440919","url":null,"abstract":"<p><p>In milk-based formulations, fat globule size is a fundamental quality parameter. Accurate measurement of globule size is critical for ensuring consistent product performance, preferably through in-line monitoring. However, most conventional techniques are off-line and unsuitable for integration into manufacturing processes. The objective of this study was to demonstrate the feasibility of a recently developed optical sensor based on Multi-Reflectance Spectroscopy (MRS) for in-line estimation of the fat globule Sauter diameter. The MRS sensor acquires multidimensional reflectance data across multiple wavelengths and defined illumination-detection geometries. Industrial validation was performed in a milk standardization plant using low-fat (1.5 wt%) and whole-fat (3.5 wt%) milk. Fat globule sizes were systematically varied by stepwise adjustment of homogenization pressure. Reference globule size distributions were obtained via analytical centrifugation and expressed as the Sauter diameter. Analytical reflectances derived from the reference size distributions were compared with experimental spectra to assess globule size dependency of the optical responses. Principal component analysis revealed a clear separation between fat concentration levels, motivating the development of concentration-specific partial least squares regression models. Two PLS models were trained and validated using independent datasets. Across the combined concentration range and full Sauter diameter span (0.7-3.5 <math><mi>μ</mi></math>m), resultet in a test RMSE of 271 nm. For the separate 1.5 and 3.5 wt% fat lines, RMSE values of approximately 80 and 40 nm were obtained, respectively. These results demonstrate that the MRS-based optical sensor enables accurate, real-time in-line monitoring of fat globule size in complex dairy emulsions and represents a promising process-analytical tool for industrial process control.</p>","PeriodicalId":8253,"journal":{"name":"Applied Spectroscopy","volume":" ","pages":"37028261440919"},"PeriodicalIF":2.2,"publicationDate":"2026-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147760573","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":"-Stacked Machine Learning for Timber Identification Using LaserInduced Breakdown Spectroscopy.","authors":"Helder V Carneiro, Erin R Price, Kierra R Cano, Caelin P Celani, James A Jordan, Kent M Elliott, Karl S Booksh","doi":"10.1177/00037028261444395","DOIUrl":"https://doi.org/10.1177/00037028261444395","url":null,"abstract":"<p><p>This study presents a new approach to wood species identification using laser-induced breakdown spectroscopy (LIBS) combined with stacked machine learning techniques. The research analyzed 700 samples comprising nine <i>Dalbergia</i> species and nine additional tropical timber species, utilizing a handheld LIBS analyzer. A stacking methodology was developed by integrating three support vector machine (SVM) models with different kernel functions (linear, polynomial, and radial) in a one-versus-all (OVA) configuration. These SVM outputs were then combined using a partial least squares discriminant analysis (PLS-DA) meta-learner. Through PCA-based variable selection, the dimensionality was reduced from 23 401 to wavelengths while maintaining classification accuracy. The stacking approach achieved a Cohen's kappa value of 0.8671 in the validation set, significantly outperforming traditional flat classifiers. Variable importance analysis revealed calcium, magnesium, and barium as crucial elements for species differentiation, with their concentrations reflecting environmental conditions and geographical origins. This research demonstrates the potential of combining LIBS spectroscopy with advanced machine learning techniques for rapid, non-invasive timber identification, which can support efforts against illegal logging and enforcement of international trade regulations.</p>","PeriodicalId":8253,"journal":{"name":"Applied Spectroscopy","volume":" ","pages":"37028261444395"},"PeriodicalIF":2.2,"publicationDate":"2026-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147760585","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":"pH-Dependent Luminescence of Flufenamic Acid Utilizing Molecular Logic Gate Operations.","authors":"N C Prachalith, K Vibha, H M Suresh Kumar, J Thipperudrappa, Udaykumar V Khadke","doi":"10.1177/00037028261438136","DOIUrl":"https://doi.org/10.1177/00037028261438136","url":null,"abstract":"<p><p>Flufenamic acid (FFA), a widely used nonsteroidal anti-inflammatory drug, is primarily recognized for its therapeutic role in pain and inflammation management. Beyond its pharmaceutical relevance, FFA exhibits pronounced pH-dependent variations in its ultraviolet-visible (UV-Vis) absorption and fluorescence spectra, which remain largely unexplored for functional material applications. In this study, the optical behavior of FFA was systematically investigated over a broad pH range (1-14), revealing distinct and reversible spectral changes driven by protonation and deprotonation processes. These pH-responsive optical features were employed to construct molecular logic gates, including implication and an improved \"INHIBIT\" (IP-INHIBIT) gate, highlighting the potential of FFA as an on-off pH sensor and a promising candidate for organic electronic applications.</p>","PeriodicalId":8253,"journal":{"name":"Applied Spectroscopy","volume":" ","pages":"37028261438136"},"PeriodicalIF":2.2,"publicationDate":"2026-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147760555","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":"Spectral Similarity Analysis of Camphor-10-Sulphonic Acid: A System Suitability Standard for Circular Dichroism in Quality Regulated Environments.","authors":"Christopher Jones","doi":"10.1177/00037028261437102","DOIUrl":"https://doi.org/10.1177/00037028261437102","url":null,"abstract":"<p><p>Spectral similarity supports comparison of circular dichroism (CD) spectra by using all datapoints to improve alignment of wavelength, intensity and offset. CD is increasingly used to confirm the higher order structure and stability of biopharmaceutical proteins, which requires method validation and assessment of robustness in quality regulated analytical systems. Camphor-10-sulphonic acid (CSA), or its ammonium salt, is widely used to calibrate spectropolarimeters, with its use specified in the European Pharmacopoeia (EP), and, more broadly, as a system suitability standard. Spectral similarity comparison of 75 CSA reference spectra in the Protein Circular Dichroism Data Bank (PCDDB) showed the potential value of this approach to monitor instrument performance and support compliance within a quality system.</p>","PeriodicalId":8253,"journal":{"name":"Applied Spectroscopy","volume":" ","pages":"37028261437102"},"PeriodicalIF":2.2,"publicationDate":"2026-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147760611","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":"Chemistry of 19th-Century Swiss Postage Stamps.","authors":"Clémence Iacconi, Lionel Rumpf, Peter Fankhauser, Cyril Portmann, Laura Hendriks","doi":"10.1177/00037028261436069","DOIUrl":"https://doi.org/10.1177/00037028261436069","url":null,"abstract":"<p><p>Despite their small size, postage stamps are culturally significant artifacts that reflect the artistic, technological, and political contexts of their production. Although the material composition of stamps from many European countries, including Italy, Portugal, and the United Kingdom, has been studied, Swiss postage stamps remain largely unexplored. In this study, we present the first systematic material characterization of 98 Swiss stamps issued between 1850 and 1908 using a combination of non-invasive analytical techniques including Raman spectroscopy, attenuated total reflection Fourier transform infrared spectroscopy (ATR FT-IR) together with scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX). In specific cases, high-performance liquid chromatography coupled with diode array detection (HPLC-DAD) was also applied. Our results highlight the predominant use of Prussian blue as a blue pigment, whereas ultramarine appears more frequently in early editions. There is greater diversity in red inks, which consist of both inorganic pigments such as vermilion, chrome orange, and red lead, and organic dyes such as eosin Y, carminic acid, and alizarin from 1882 onwards. Yellow and green inks reflect standard formulations, the latter resulting from the combination of Prussian blue and chrome yellow, broadly corresponding to those used in contemporary foreign issues. Brown and gray inks were obtained from a mixture of carbon black and a red or white pigment, respectively. This study sheds new light on the material history of Swiss postage stamps and highlights the value of combining spectroscopy, imaging, and chromatography techniques in philatelic research and, more broadly, in heritage science.</p>","PeriodicalId":8253,"journal":{"name":"Applied Spectroscopy","volume":" ","pages":"37028261436069"},"PeriodicalIF":2.2,"publicationDate":"2026-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147760603","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":"Infrared Reflection Spectra of Quartz at Out-of-Plane Orientations: Validating Lekner's Expression for Anisotropic Materials.","authors":"Yuko Amaki, Naoto Nagai, Takeshi Yamauchi","doi":"10.1177/00037028261438158","DOIUrl":"https://doi.org/10.1177/00037028261438158","url":null,"abstract":"<p><p>It has long been of interest to understand how optical spectra change when the principal axis of a uniaxial crystal is oriented not only within the measurement plane but also out of the plane. Although several theoretical frameworks have been developed to address this situation, relatively few studies have directly compared these models with experimentally measured spectra. In this study, Lekner's formalism, which is applicable when the principal axes are not confined to the measurement plane, was applied to crystalline quartz. The reliability of this method for three-dimensional orientation analysis of uniaxial crystals was evaluated by comparing calculated reflection spectra with experimental measurements. The results showed that large frequency dispersion produces orientation-dependent spectral features. These features arise from the mixing of the optical responses along the principal axes when out-of-plane orientations are present. The potential and limitations of this approach for determining crystal orientation angles are also discussed.</p>","PeriodicalId":8253,"journal":{"name":"Applied Spectroscopy","volume":" ","pages":"37028261438158"},"PeriodicalIF":2.2,"publicationDate":"2026-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147728157","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}