Spectroscopy Letters最新文献

{"title":"Vibrational spectroscopic, electronic influences, reactivity analysis and molecular docking studies of 2-Fluoro-4-iodo-5-methylpyridine","authors":"S. Selvakumari, C. Venkataraju, S. Muthu, P. Sangeetha, R. Rajesh","doi":"10.1080/00387010.2022.2160462","DOIUrl":"https://doi.org/10.1080/00387010.2022.2160462","url":null,"abstract":"Abstract Geometrical optimization along with spectroscopic survey and electronic scrutiny of 2-Fluoro-4-iodo-5-methylpyridine were carried out by exercising Density-functional theory. The intramolecular hydrogen bonding interaction of the caption compound was investigated by means of the Natural Bond Orbital analysis. The Highest Occupied Molecular Orbital & Lowest Unoccupied Molecular Orbital energies, Mulliken charges, and Non-Linear Optic properties were procured in dissimilar liquids to analyze the solvent influence. The Theoretic Ultraviolet-visible spectrum of the investigation compound has been accomplished using Time-dependent density-functional theory in different solvents chosen. A Molecular Electrostatic Potential study has been achieved and conferred in terms of color distribution shows the reactive regions for protein interactions. Additionally, Electron localization function, Localized orbital locator and Reduced density gradient analysis of the caption compound were also studied. Furthermore, to reveal the biological importance of the caption compound, drug-likeness parameters have been computed and docking of the heading compound into the energetic site of the target proteins were performed to confirm that this compound has drug behavior.","PeriodicalId":21953,"journal":{"name":"Spectroscopy Letters","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2022-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44864279","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Correlations between lipid contents of natural rubber and tensile properties of natural rubber-based compound, using attenuated total reflection Fourier transform infrared spectroscopy","authors":"Zohreh Asghari Barzegar, S. Taghvaei Ganjali, M. Malekzadeh, F. Motiee","doi":"10.1080/00387010.2022.2153143","DOIUrl":"https://doi.org/10.1080/00387010.2022.2153143","url":null,"abstract":"Abstract In this study, the lipid contents of different kinds of natural rubber were measured by attenuated total reflection–Fourier transform infrared spectroscopy. The correlation between these amounts were considered with the tensile properties of natural rubber compounds. The Pearson correlation coefficients were more than −0.9 for all cases, which confirms that the models are acceptable. These models were applied for the estimation of tensile properties in the case study. It was observed that the tensile strength, elongation at break, modulus 100%, and modulus 300% can be predicted by errors of about 4%, 17%, 18%, and 18% respectively. This is a simple, fast, and nondestructive way to estimate the tensile properties before the compound preparation.","PeriodicalId":21953,"journal":{"name":"Spectroscopy Letters","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2022-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42269741","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A novel fluorescent probe for copper (II) ion based on rare earth polyoxometalate","authors":"Na Li, Xiaowen Chen, Yulan Huang, Li Wang, J. Li, Xiangxiang Yang","doi":"10.1080/00387010.2022.2143819","DOIUrl":"https://doi.org/10.1080/00387010.2022.2143819","url":null,"abstract":"Abstract A new strategy for the determination of Cu(II) ions was developed using K10H3[Eu(SiMo6W5O39)2]·28H2O. The polyoxometalate H4SiMo6W6O40 acts as a ligand to sensitize the europium ion to emit red fluorescence, and the fluorescence was quenched by the addition of Cu(II) ions. The luminescence of the central Eu3+ was quenched due to the inner filter effect (IFE) of Cu(II) to K10H3[Eu(SiMo6W5O39)2]·28H2O and the static burst. Therefore, K10H3[Eu(SiMo6W5O39)2]·28H2O can be used as a specific fluorescent probe for Cu2+ and it exhibited a very good linear response range for copper ions from 1 to 20 μM with detection limit of 0.13 µM. The probe was successfully applied to the determination of Cu(II) ions in clam samples with recoveries in the range of 90–98%.","PeriodicalId":21953,"journal":{"name":"Spectroscopy Letters","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2022-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43682354","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Monitoring the leaf equivalent water thickness of kiwifruit in high temperature using leaf spectral reflectance","authors":"Zhen Zhang, Yu Fu, Hualong Li, Jianping Guo, Yuying Pan, Yong Zhang, Weimin Zhang, Jing-hong Wang, Yuefeng Liu, Lu Liu","doi":"10.1080/00387010.2022.2149558","DOIUrl":"https://doi.org/10.1080/00387010.2022.2149558","url":null,"abstract":"Abstract Leaf water status information is highly needed for assessing high temperature stress. Leaf equivalent water thickness (fresh weight − dry weight)/area) is commonly used functional plant trait. Retrieval of leaf equivalent water thickness based on hyperspectral remote sensing has been shown to be rapid and accurate. However, a universal index that is applicable to various plants remains a considerable challenge. Few attempts had been made to monitor kiwifruit leaf equivalent water thickness using hyperspectral vegetation indexes under high temperature stress. In this study, a high temperature stress experiment was conducted in ambient conditions on 29 July–1 August 2021 during the kiwifruit expansion period to obtain a leaf spectrum dataset in the laboratory after the high temperature (above 35 °C) duration time for 1, 2, 3, and 4 days. This study systematically analyzed the performance of hyperspectral vegetation indexes of kiwifruit in estimating leaf equivalent water thickness with the range of 0.02–0.04 g/cm2. Newly developed and published spectral indexes were calculated to estimate kiwifruit leaf equivalent water thickness. Results showed that the newly developed three-band vegetation index (R2039 − R2438)/R752 generated the optimal testing performance for estimating kiwifruit leaf equivalent water thickness, with the coefficient of determination of 0.771, root mean square error of 0.0024 g/cm2, and residual prediction deviation of 2.09, respectively. This study suggests that the kiwifruit leaf equivalent water thickness under high temperature stress could be accurately estimated based on leaf level spectral indexes.","PeriodicalId":21953,"journal":{"name":"Spectroscopy Letters","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2022-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42679201","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Molecular structure, molecular docking and vibrational spectra of 2,2′-[1,3,5,7-tetraoxo-5,7-dihydropyrrolo[3,4-f-[isoindole 2,6(1H,3H) diyl]]] diacetohydrazide molecule by density functional theory approach as human immunodeficiency virus inhibitory","authors":"D. Kafi, A. Ayyash","doi":"10.1080/00387010.2022.2139726","DOIUrl":"https://doi.org/10.1080/00387010.2022.2139726","url":null,"abstract":"Abstract Molecular structure, molecular docking, and vibrational spectra of 2,2′-[1,3,5,7-tetraoxo-5,7-dihydropyrrolo[3,4-f-[isoindole 2,6(1H,3H) diyl]]] diacetohydrazide molecule by density functional theory approach as human immunodeficiency virus inhibitory. Despite several investigations into anti-human immunodeficiency virus therapy, human immunodeficiency virus infection remains difficult to treat due to drug resistance. The emergence of new human immunodeficiency virus mutations has resulted in drug rejection versus Food and Drug Administration recommended drugs already in use reduced efficacy against the human immunodeficiency virus. On this basis, the density functional theory approach on B3LYP/6-311G(d,p) levels was used to determine the molecular properties of 2,2′-[1,3,5,7-tetraoxo-5,7-dihydropyrrolo[3,4-f-[isoindole 2,6(1H,3H) diyl]]] diacetohydrazide molecule. The geometric analysis values were fitted to the experimental data characterizing the stable structure of the molecule, and the molecular structure (bond length, bond angle and dihedral angle) was then determined. Electronic properties of molecular orbits (the highest occupied molecular orbital and the lowest unoccupied molecular orbital) have been studied. The calculated Fourier transform infrared and hydrogen nuclear magnetic resonance vibrational frequencies agreed well with the experimentally obtained frequencies. The inhibitory ability of the compound under study was evaluated in a molecular docking assay against the human immunodeficiency virus protein. The carbonyl group of the molecule has been shown to be critical for antiviral activity. The high binding energy (−9.40 kcal/mol) also indicates the significant antiviral activity.","PeriodicalId":21953,"journal":{"name":"Spectroscopy Letters","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2022-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44283393","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Jatropha integerrima flower extract mediated green synthesis of silver nanoparticles: spectroscopic, catalytic, and antioxidant analysis","authors":"A. Bala, G. Rani, R. Ahlawat","doi":"10.1080/00387010.2022.2137200","DOIUrl":"https://doi.org/10.1080/00387010.2022.2137200","url":null,"abstract":"Abstract Plant extract mediated nanoparticles have gained enormous attention for their green and rational approach and developed as an alternative to conventional chemical and physical methods. Here, the less exploited Jatropha integerrima flower extract is used in the synthesis of silver nanoparticles. The as-prepared nanoparticles exhibit a strong surface plasma resonance around 420 nm. Several spectroscopic techniques confirmed the formation of silver nanoparticles with an average size of 32.07 nm, stabilized by functional groups. The catalytic activity of synthesized nanoparticles for Rhodamine B dye degradation in the presence of sodium borohydride was investigated. The results showed that the 100 µL catalyst dose degraded the alkaline solution of dye up to 98%, with a high rate constant of 1.2110 min−1. In addition, the nanoparticles were tested for antioxidant activity using the 2,2-dipehnyl-1-picrylhydrazyl free radical assay. The calculated IC50 value for synthesized nanoparticles was 33.63 ± 0.53 µg/mL. Thus, the as-prepared nanoparticles are excellent candidates for catalytic and antioxidant activities compared to other materials used so far.","PeriodicalId":21953,"journal":{"name":"Spectroscopy Letters","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2022-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48074374","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Selecting near-infrared reflection spectroscopy pretreatment methods by chemical components valid and invalid absorption wavebands","authors":"Tiancheng Huang, Guimin Cai, Hubin Liu, Zhiyue Feng, Longlian Zhao, Junhui Li","doi":"10.1080/00387010.2022.2136200","DOIUrl":"https://doi.org/10.1080/00387010.2022.2136200","url":null,"abstract":"Abstract An appropriate pretreatment method is crucial to establish a reliable model for near-infrared spectroscopy. It is usually selected by comparing model performance with different pretreatment methods, such as the root mean square error of internal cross-validation or the root mean square error of prediction. When the statistical indexes of the models are similar and indistinguishable, or the results of model calibration and cross-validation are too different, indicating an overfitting situation, it may be due to the selection of an inappropriate pretreatment. In this paper, an approach is proposed to select appropriate pretreatment methods by chemical components valid and invalid absorption wavebands. Due to there being no chemical groups absorption in wavebands of 1250–1350 nm and 1780–1850 nm, they are considered chemical invalid absorption bands. The root mean square distance in the invalid wavebands characterizes the difference in samples’ physical state, such as particle size and instrument error. Except for the invalid absorption band, other wavebands in the near-infrared region are considered chemical valid absorption wavebands. The root mean square distance in the valid absorption wavebands mainly characterize the chemical composition differences between different samples. So, we define effective information rate of spectra. The larger effective information rate of spectra, the more favorable it is to establish a quantitative model. In this study, spectra of 60 wheat powder samples were used to compare seven pretreatment methods. Moreover, the average effective information rates of spectra were calculated for the seven pretreatment methods respectively. The results show that the combination of standard normal variate transformation and first derivative with Savitzky–Golay smoothing is the best. Finally, a comparison of model prediction with different pretreatment methods was made. The results are the same as the former. Therefore, using the effective information rate of spectra for selecting an appropriate near-infrared spectroscopy pretreatment method is practical and can be used not only for near-infrared modeling but also for designing near-infrared instruments as an index for optimization.","PeriodicalId":21953,"journal":{"name":"Spectroscopy Letters","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2022-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49457468","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spectroscopic and computational approach to study the interacting mechanism of drug-adenine complex","authors":"Chiging Sonia, T. Devi, T. Karlo","doi":"10.1080/00387010.2022.2131826","DOIUrl":"https://doi.org/10.1080/00387010.2022.2131826","url":null,"abstract":"Abstract The biomolecular complex, Adenine and Rheumatoid Arthritis drug are characterized using vibrational spectroscopy and density functional theory. The spectral characterization of the biomolecule is undertaken by using Fourier transform infrared spectroscopy, Raman and surface-enhanced Raman spectroscopy techniques. The optimization and theoretical calculation of the molecules are performed using the density functional theory method. The frontier molecular orbital, molecular electrostatic potential, natural bond orbital parameters, thermodynamic properties, and first-order hyperpolarizability of the adenine monomer, hydroxychloroquine monomer, and their interacting state are calculated by Becke–Lee–Yang–Parr method with a basis set of 6-311G + (d, p). The Quantum Theory Atoms in Molecules study is performed for investigating the topological parameters, such as the density of electrons, the Laplacian of electron density, and the energy density. The vibrational assignment of the individual and interacting molecules is accomplished through the Vibrational Energy Distribution Analysis program. The theoretical and experimental values show good agreement with one another. The drug-likeliness behavior of the biomolecular complex is also studied. The molecular docking studies of the molecules are carried out against human synovial fluid sPLA2 to determine the best binding sites.","PeriodicalId":21953,"journal":{"name":"Spectroscopy Letters","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2022-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49243155","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Rapid determination of Panax notoginseng origin by terahertz spectroscopy combined with the machine learning method","authors":"Huo Zhang, Lanjuan Huang, Chuan-pei Xu, Zhi Li, Xianhua Yin, Tao Chen, Yuee Wang","doi":"10.1080/00387010.2022.2125017","DOIUrl":"https://doi.org/10.1080/00387010.2022.2125017","url":null,"abstract":"Abstract Panax notoginseng is a valuable herb with geographical indication, and the quality and price of P. notoginseng from different origins are very different. Therefore, this paper proposes a rapid and accurate method for identifying the origins of P. notoginseng by collecting the roots of P. notoginseng. This paper improves the whale optimization algorithm in terms of global convergence and convergence speed, introduces the Levy flight strategy and reconstructed whale synergy factor A, and applies it to the parameter optimization of support vector machines, to obtain a high-performance classification model. The improved whale optimization algorithm model identifies the origin of P. notoginseng by discriminating their terahertz spectra. Compared with the commonly used genetic algorithm and the original whale optimization algorithm, improvement in the whale optimization algorithm was able to avoid falling into local optimum solutions more effectively while having a high convergence rate. Accordingly, the improved whale optimization algorithm optimized support vector machine model obtained an overall accuracy of 98.44%, which was significantly higher than the 95.31% overall accuracy of the genetic algorithm optimized support vector machine model and the 96.88% overall accuracy of the whale optimization algorithm optimized support vector machine model. It was concluded that terahertz spectroscopy together with machine learning would be a promising technique for identifying the origins of P. notoginseng.","PeriodicalId":21953,"journal":{"name":"Spectroscopy Letters","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2022-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43077007","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Femtosecond excitation of two-photon absorption in ruby","authors":"W. Hardin, Jon. T. Mills, Joseph M. Stuart, Eian B. Sulfridge, Tyler A. Tanner, Thomas W. Jarvis","doi":"10.1080/00387010.2022.2123000","DOIUrl":"https://doi.org/10.1080/00387010.2022.2123000","url":null,"abstract":"Abstract We report two-photon absorption in ruby in an experiment simple enough to reproduce in an undergraduate optics course. The high peak power of a femtosecond (fs) pulse from an unamplified titanium:sapphire laser is sufficient to drive a two-photon transition to ruby’s broad absorption bands, with subsequent emission at 694 nm from the metastable state. This experiment uses pulses with tens of nanojoules rather than the tens or hundreds of millijoules required for nanosecond experiments, and can be performed with trivial instrumentation – eliminating photomultiplier tubes in favor of simple, inexpensive photodiodes with no amplification or signal processing. A two-photon measurement provides excellent educational value for undergraduate students and expands the repertoire of pedagogical optics experiments in an interesting direction.","PeriodicalId":21953,"journal":{"name":"Spectroscopy Letters","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2022-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49254686","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}