Applied Spectroscopy最新文献

{"title":"Half-Inch Monolithic Spatial Heterodyne Raman Spectrometer: A Study of Polarized Raman Spectra of Organic Liquids and Instrumental Performance.","authors":"Evan M Kelly, Miles J Egan, Arelis Colόn, S Michael Angel, Shiv K Sharma","doi":"10.1177/00037028241257961","DOIUrl":"10.1177/00037028241257961","url":null,"abstract":"<p><p>Raman spectroscopy allows for the unambiguous identification of materials through the inelastic scattering of light. This technique has a great many uses in various aspects of society from academic, scientific, and industry. This paper explores a specific type of Raman spectrometer called a spatial heterodyne Raman spectrometer (SHRSy), which is a variation of an interferometric spectrometer. It utilizes a Michelson interferometer and replaces the mirrors with gratings that transform it from a time-domain spectrometer to a spatial-domain spectrometer, allowing for the entirety of the spectrum to be captured at once. This study specifically tests a half-inch two-grating monolithic SHRS (½-in. 2g-mSHRS), which has a weight of <60 g and a size of 2.2 × 2.2 × 1.3 cm. To do this we excite a variety of organic liquids with a 532 nm neodymium-doped yttrium aluminum garnet (Nd:YAG) pulsed laser, using an excitation energy of 6.5 mJ/pulse and distance of 3 m in conjunction with an intensified charge-coupled device camera. This is the first time that the SHRS has been used for investigating polarized Raman spectra of liquids. We discuss and contrast the instrumental properties such as resolution, spectral range, étendue, and field of view with previously tested mSHRS to give context to the instrument's performance.</p>","PeriodicalId":8253,"journal":{"name":"Applied Spectroscopy","volume":" ","pages":"1062-1070"},"PeriodicalIF":2.2,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141295471","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":"Advertising and Front Matter.","authors":"","doi":"10.1177/00037028241292113","DOIUrl":"https://doi.org/10.1177/00037028241292113","url":null,"abstract":"","PeriodicalId":8253,"journal":{"name":"Applied Spectroscopy","volume":"78 10","pages":"1009-1014"},"PeriodicalIF":2.2,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142456783","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":"Coomassie Brilliant Blue G for Smart Colorimetric Determination of the Ionic Surfactants in Triton X-100 Solutions.","authors":"Liudmyla Korzhan, Sergey Kulichenko, Serhii Lelyushok, Viktoriia Klovak","doi":"10.1177/00037028241267900","DOIUrl":"10.1177/00037028241267900","url":null,"abstract":"<p><p>The conditions for the smart colorimetric determination of cetylpyridinium chloride and sodium dodecyl sulfate by reaction with Coomassie brilliant blue G (CBBG) have been proposed. The nature of the absorption and fluorescence spectra of aqueous solutions of CBBG as a function of acidity has been investigated. A variety of reagent forms and associations with ionic surfactants have been demonstrated. The composition of the associates formed in the CBBG-cationic surfactant system has been established. The increase in the analytical signal of the cationic surfactant and the stabilization of the colloid-chemical state of the system during reactions in the organized medium of the nonionic surfactant Triton X-100 has been demonstrated. These effects are realized through association in premicellar solutions and as a result of the solubilization of components in Triton X-100 micellar solutions. The addition of long-chain cationic surfactants to the reagent occurs with the replacement of the heteroatom proton. The absorption of CBBG-cationic surfactant associates solutions increases with the length of the cationic surfactant hydrocarbon chain. Ethanol additives decrease the aggregation of CBBG. The technique of cationic surfactant determination has been tested in the analysis of the pharmaceutical. The results show that the simplicity of analytical signal registration with satisfactory correctness and acceptably high sensitivity of determination is an advantage of the developed technique.</p>","PeriodicalId":8253,"journal":{"name":"Applied Spectroscopy","volume":" ","pages":"1105-1114"},"PeriodicalIF":2.2,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141878254","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":"Photoacoustic Spectroscopy of Titanium Dioxide, Niobium Pentoxide, Titanium:Niobium, and Ruthenium-Modified Oxides Synthesized Using Sol-Gel Methodology.","authors":"Daniele T Dias, Andressa O Rodrigues, Pietra B Pires, Betina C Semianko, Maria E K Fuziki, Giane G Lenzi, Simone R F Sabino","doi":"10.1177/00037028241268158","DOIUrl":"10.1177/00037028241268158","url":null,"abstract":"<p><p>The aim of this work was the development and morphological/chemical, spectroscopic, and structural characterization of titanium dioxide, niobium pentoxide, and titanium:niobium (Ti:Nb) oxides, as well as materials modified with ruthenium (Ru) with the purpose of providing improvement in photoactivation capacity with visible sunlight radiation. The new materials synthesized using the sol-gel methodology were characterized using the following techniques: scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), photoacoustic spectroscopy (PAS), and X-ray diffraction (XRD). The SEM-EDS analyses showed the high purity of the bases, and the modified samples showed the adsorption of ruthenium on the surface with the crystals' formation and visible agglomerates for higher calcination temperature. The nondestructive characterization of PAS in the ultraviolet visible region suggested that increasing calcination temperature promoted changes in chemical structures and an apparent decrease in gap energy. The separation of superimposed absorption bands referring to charge transfers from the ligand to the metal and the nanodomains of the transition metals suggested the possible absorption centers present at the absorption threshold of the analyzed oxides. Through the XRD analysis, the formation of stable phases such as T-Nb_16.8O₄₂, <i>o</i>-Nb₁₂O₂₉, and rutile was observed at a lower temperature level, suggesting pore induction and an increase in surface area for the oxides studied, at a calcination temperature below that expected by the related literature. In addition, the synthesis with a higher temperature level altered the previously existing morphologies of the Ti:Nb, base and modified with Ru, forming the new mixed crystallographic phases Ti₂Nb₁₀O₂₉ and TiNb₂O₇, respectively. As several semiconductor oxide applications aim to reduce costs with photoexcitation under visible light, the modified Ti:Ru oxide calcined at a temperature of 800 °C and synthesized according to the sol-gel methodology used in this work is suggested as the optimum preparation point. This study presented the formation of a stable crystallographic phase (rutile), a significant decrease in gap energy (2.01 eV), and a visible absorption threshold (620 nm).</p>","PeriodicalId":8253,"journal":{"name":"Applied Spectroscopy","volume":" ","pages":"1028-1042"},"PeriodicalIF":2.2,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141878259","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":"In Situ Quantification of Carbonate Species Concentrations, pH, and pCO₂ in Calcite Fluid Inclusions Using Confocal Raman Spectroscopy.","authors":"Michael Naylor Hudgins, Todd K Knobbe, Julia Hubbard, Andrew Steele, Justin G Park, Morgan F Schaller","doi":"10.1177/00037028241275192","DOIUrl":"10.1177/00037028241275192","url":null,"abstract":"<p><p>Carbonate minerals are globally distributed on the modern and ancient Earth and are abundant in terrestrial and marine depositional environments. Fluid inclusions hosted by calcite retain primary signatures of the source fluid geochemistry at the time of mineral formation (i.e., pCO₂) and can be used to reconstruct paleoenvironments. Confocal laser Raman spectroscopy provides a quick, nondestructive approach to measuring the constituents of fluid inclusions in carbonates and is a reliable method for qualitatively determining composition in both the aqueous and gas phases. Here, we demonstrate a method for accurately quantifying bicarbonate and carbonate ion concentrations (down to 20 mM) and pH (7-11) from calcite fluid inclusions using confocal Raman spectroscopy. Instrument calibrations for carbonate (CO₃^2-) and bicarbonate (HCO₃^-) concentrations and pH were performed using stock solutions. We show that the calcite host mineral does not affect the accurate quantification of carbonate solution concentrations and that these parameters can be used to estimate the pH and pCO₂ of a solution entrapped within a fluid inclusion. We apply the technique to Icelandic spar calcite and find a [CO₃^2-] = 0.11, [HCO₃^-] = 0.17, pH = 10.1, and CO₂ parts per million = 2217. The presence of gaseous Raman bands for CO₂, CH₄, and H₂S suggests that the mineral precipitated in a reducing environment.</p>","PeriodicalId":8253,"journal":{"name":"Applied Spectroscopy","volume":" ","pages":"1015-1027"},"PeriodicalIF":2.2,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142139140","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":"Estimation of the Global Equivalence Ratio of a Swirl Combustor from a Small Number of Absorption Spectra Using Machine Learning.","authors":"Cheolwoo Bong, Seong-Kyun Im, Hyungrok Do, Moon Soo Bak","doi":"10.1177/00037028241268279","DOIUrl":"10.1177/00037028241268279","url":null,"abstract":"<p><p>A new optical diagnostic method that predicts the global fuel-air equivalence ratio of a swirl combustor using absorption spectra from only three optical paths is proposed here. Under normal operation, the global equivalence ratio and total flow rate determine the temperature and concentration fields of the combustor, which subsequently determine the absorption spectra of any combustion species. Therefore, spectra, as the fingerprint for a produced combustion field, were employed to predict the global equivalence ratio, one of the key operational parameters, in this study. Specifically, absorption spectra of water vapor at wavenumbers around 7444.36, 7185.6, and 6805.6 cm^-1 measured at three different downstream locations of the combustor were used to predict the global equivalence ratio. As it is difficult to find analytical relationships between the spectra and produced combustion fields, a predictive model was a data-driven acquisition. The absorption spectra as an input were first feature-extracted through stacked convolutional autoencoders and then a dense neural network was used for regression prediction between the feature scores and the global equivalence ratio. The model could predict the equivalence ratio with an absolute error of ±0.025 with a probability of 96%, and a gradient-weighted regression activation mapping analysis revealed that the model leverages not only the peak intensities but also the variations in the shape of absorption lines for its predictions.</p>","PeriodicalId":8253,"journal":{"name":"Applied Spectroscopy","volume":" ","pages":"1078-1088"},"PeriodicalIF":2.2,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141874038","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":"Redefining Spectral Data Analysis with Immersive Analytics: Exploring Domain-Shifted Model Spaces for Optimal Model Selection.","authors":"Jordan M J Peper, John H Kalivas","doi":"10.1177/00037028241280669","DOIUrl":"https://doi.org/10.1177/00037028241280669","url":null,"abstract":"<p><p>Modern developments in autonomous chemometric machine learning technology strive to relinquish the need for human intervention. However, such algorithms developed and used in chemometric multivariate calibration and classification applications exclude crucial expert insight when difficult and safety-critical analysis situations arise, e.g., spectral-based medical decisions such as noninvasively determining if a biopsy is cancerous. The prediction accuracy and interpolation capabilities of autonomous methods for new samples depend on the quality and scope of their training (calibration) data. Specifically, analysis patterns within target data not captured by the training data will produce undesirable outcomes. Alternatively, using an immersive analytic approach allows insertion of human expert judgment at key machine learning algorithm junctures forming a sensemaking process performed in cooperation with a computer. The capacity of immersive virtual reality (IVR) environments to render human comprehensible three-dimensional space simulating real-world encounters, suggests its suitability as a hybrid immersive human-computer interface for data analysis tasks. Using IVR maximizes human senses to capitalize on our instinctual perception of the physical environment, thereby leveraging our innate ability to recognize patterns and visualize thresholds crucial to reducing erroneous outcomes. In this first use of IVR as an immersive analytic tool for spectral data, we examine an integrated IVR real-time model selection algorithm for a recent model updating method that adapts a model from the original calibration domain to predict samples from shifted target domains. Using near-infrared data, analyte prediction errors from IVR-selected models are reduced compared to errors using an established autonomous model selection approach. Results demonstrate the viability of IVR as a human data analysis interface for spectral data analysis including classification problems.</p>","PeriodicalId":8253,"journal":{"name":"Applied Spectroscopy","volume":" ","pages":"37028241280669"},"PeriodicalIF":2.2,"publicationDate":"2024-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142340056","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":"Two-Dimensional Correlation Spectroscopy (2D-COS) Tracking of the Formation of Selected Transition Metal Compounds Cu(II) and Cd(II) With Cinchonine and Their Impact on Model Components of Erythrocytes","authors":"Zofia Chajdaś, Martyna Kucharska, Aleksandra Wesełucha-Birczyńska","doi":"10.1177/00037028241279434","DOIUrl":"https://doi.org/10.1177/00037028241279434","url":null,"abstract":"Cinchonine is a quinoline alkaloid known for its antimalarial properties. Due to the advantages of using compounds of metal ions with alkaloids, a copper(II) compound with cinchonine was synthesized, and, for comparative purposes, a cadmium(II) compound with cinchonine. During the synthesis, the emerging interactions between the metal ion and cinchonine were studied. After crystallization, it was examined how the obtained compounds would interact with the model blood component, hematoporphyrin IX. Ultraviolet–visible (UV–Vis) spectroscopy, Raman spectroscopy, and attenuated total reflection Fourier transform infrared spectroscopy (ATR FT-IR) were used in the study. In the case of monitoring the synthesis, the best method turned out to be UV–Vis spectroscopy, combined with the possibility of two-dimensional correlation spectroscopy (2D-COS), which enabled the identification of peaks characteristic of the interactions of the cinchonine quinoline ring with metal ions. In turn, the obtained Raman spectra showed shifts of individual bands and changes in their intensity, and 2D-COS showed the sequence of formation of individual interactions, which confirmed the formation of cinchonine compounds with metals. ATR FT-IR also allowed us to compare the spectra of the substrates used in the synthesis with the crystallized compounds and thus confirm the formation of the expected compounds. Bands characteristic of π–π-stacking interactions between the quinoline ring and the tetrapyrrole ring of hematoporphyrin IX were also observed. Observed interaction with a model blood component may be important when designing drugs for antimalarial therapy.","PeriodicalId":8253,"journal":{"name":"Applied Spectroscopy","volume":"95 1","pages":"37028241279434"},"PeriodicalIF":3.5,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142263028","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":"Glioma Identification Based on Digital Multimodal Spectra Integrated With Deep Learning Feature Fusion Using a Miniature Raman Spectrometer","authors":"Qingbo Li, Shufan Chen","doi":"10.1177/00037028241276013","DOIUrl":"https://doi.org/10.1177/00037028241276013","url":null,"abstract":"The miniature fiber Raman spectroscopy detection technology can reflect the properties of biomolecules through spectral characteristics and has the advantages of noninvasiveness, real-time, safety, label-free operation, and potential for early cancer diagnosis. This technology holds promise for developing portable, low-cost, intraoperative tumor detection instruments. Glioma is one of the most common malignant tumors of the central nervous system with rapid growth and a short disease course. However, the considerable heterogeneity of the glioma sample leads to substantial intraclass variance in collected spectra, coupled with the miniature Raman spectrometer's low signal-to-noise ratio. These factors diminish the accuracy of the brain glioma recognition model. To address this issue, a glioma identification method based on digital multimodal spectra integrated with deep learning features fusion (DMS-DLFF) using the miniature Raman spectrometer is proposed. Different from existing multimodal tumor detection methods employing multiple spectral instruments, DMS-DLFF enhances tumor identification accuracy without increasing hardware costs. The method mathematically decomposes the original spectra to Raman and fluorescence spectra, so as to augment the biospectral information. Then, the deep learning method is used to extract the feature information of the two kinds of spectra, respectively, and the digital multimodal spectral fusion is realized at the feature level. Moreover, a two-layer pattern recognition model is constructed based on the ensemble strategy, amalgamating the strengths of diverse classifiers. Meanwhile, the bagging strategy is introduced to improve support vector machine algorithms, one of the basic classifiers. Compared with traditional methodologies, DMS-DLFF operates at both the feature level and decision level, employing high-information-density feature vectors to train ensemble classification models for increasing overall recognition accuracy. This study collected 260 Raman spectra of glioma and 151 Raman spectra of normal brain tissue. The accuracy, sensitivity, and specificity were 91.9%, 96.7%, and 80.8%, respectively. The proposed method outperforms traditional algorithms in brain glioma detection, which helps doctors formulate precise surgical plans and thereby improve patient prognosis.","PeriodicalId":8253,"journal":{"name":"Applied Spectroscopy","volume":"1 1","pages":"37028241276013"},"PeriodicalIF":3.5,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142214319","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":"Characterization of Orthophosphate and Orthovanadate in Aqueous Solution Using Polarized Raman Spectroscopy.","authors":"Wolfram Rudolph","doi":"10.1177/00037028241275107","DOIUrl":"https://doi.org/10.1177/00037028241275107","url":null,"abstract":"<p><p>Polarized Raman spectroscopy was used to analyze aqueous solutions of sodium orthophosphate and orthovanadate over a wide concentration range (0.00891-0.702 mol/L) at 23 °C. The isotropic scattering profiles were obtained by measuring polarized Raman scattering spectra. Furthermore, R-normalized spectra were calculated and presented. The tetrahedral ions, VO₄^3-(aq) and PO₄^3-(aq), demand four Raman active bands which have been subsequently characterized and assigned. For the PO₄^3-(aq) ion, the deformation modes ν₂(e) and ν₄(f₂) appear at 415 and 557 cm^-1, and these modes are depolarized. In the P-O stretching region, the strongest Raman band appears at 936.5 cm^-1, which is totally polarized with a depolarization ratio (ρ-value) of 0.002. The broad and depolarized mode at 1010 cm^-1 constitutes the antisymmetric stretching band ν₃(f₂). The Raman spectrum of VO₄^3- shows two depolarized deformation modes ν₂(e) and ν₄(f₂) at 327 and 345.6 cm^-1, which are severely overlapped. These bands are very weak. The strongest band in the Raman spectrum of VO₄^3-(aq) is the symmetric stretching mode ν₁(a₁) at 820.2 cm^-1 which is totally polarized with a ρ-value at 0.004. The depolarized antisymmetric stretching mode ν₃(f₂) appeared at 785 cm^-1 as a broad and weak band. Both anions are strongly hydrated and showed extensive hydrolysis in an aqueous solution. Orthovanadate is a much stronger base than orthophosphate in aqueous solution. Therefore, a large amount of NaOH was used to suppress the hydrolysis of VO₄^3-(aq) sufficiently, so, it was possible to characterize the VO₄^3- modes. Quantitative Raman spectroscopy was applied to follow the hydrolysis of PO₄^3- over a wide concentration range from 0.00891 to 0.592 mol/L. The hydrolysis data allowed the calculation of the p<i>K</i>_a3 value for H₃PO₄ to be 12.330 ± 0.02 (25 °C). The hydrolysis of the VO₄^3- ion is ∼21 times larger than that of the PO₄^3-. The p<i>K</i>_a3 value for H₃VO₄ is estimated to be 13.65 ± 0.1 (25 °C).</p>","PeriodicalId":8253,"journal":{"name":"Applied Spectroscopy","volume":" ","pages":"37028241275107"},"PeriodicalIF":2.2,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142139139","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}