| It is of far-reaching practical significance to use Raman spectroscopy technology to study organics.And Raman spectroscopy itself is a kind of non-destructive testing method with advantages of microscopic,in-situ,good stability,high sensitivity and high spatial resolution.Therefore,the commonalities and differences are obtained by studying the Raman spectroscopic characteristics of saturated monohydroxy alcohols.Based on this,we summarized the vibration and rotation information at the molecular level,which provided theoretical and experimental support for the detection and further study of saturated monohydric alcohols.In addition,due to the influence of external factors,some organic components that may harm human health may be introduced into foods,medicines,and the environment.However,they are often trace levels,and it is difficult to achieve identificati on only relying on Raman spectroscopy.Surface Enhanced Raman Scattering(SERS)spectroscopy needs to be introduced to enhance the weak Raman signal for detection.Surface-enhanced Raman spectroscopy can be used to detect subtle changes in a variety of systems and analyze organic species and content.Therefore,In this paper,we perform clustering discrimination and quantitative identification of isomers,by studying the similarities and differences between several saturated monohydric alcohols through Raman spectroscopy.Quantitative modeling and prediction of Iminophos in water have been obtained based on Surface Enhanced Raman.The specific work is as follows:1.The experimentally measured Raman spectra of the nine saturated monohydric alcohols were combined with the Raman spectra calculated by density functional theory.Through comparative analysis,we choose four major Raman bands by studying the assignment of the characteristic Raman peaks.Through analyzing their principal components and calculating their Euclidean distance,we can distinguish nine saturated monohydroxy alcohols exactly(the recognition is 100%).2.Based on the variation of the characteristic Raman peaks of three alcohols isomers with different doping ratios,the univariate and multivariate analysis methods were used to quantitatively analyze the changes.Based on the Gaussian linear characteristics of the Raman band waveform,the basic peak of the vibrational stretching of the OH group were decomposed by the multi-peak fitting method,and then the hydrogen bond changes between the isomers were explored.3.Surface enhanced Raman spectroscopy is indispensable for the analysis and detection of low concentrations of organics.Because of the different enhancement effects of different substrates and in order to distinguish the differences and select suitable reinforcing substrates for the reagents,three substrates were selected for production studies to explore the differences between their enhancement effects.The three bases are all impr oved based on the reduction method used by Lee et al.They are sodium citrate,sodium borohydride,and hydroxylamine hydrochloride,respectively,serving as reducing agents.Selecting methyl violet solution as the probe reagent,the characteristics of Rama n peaks of the three kinds of substrate-enhanced probe reagents before and after were obtained,and the enhancement efficiency and signal-to-noise ratio of each substrate were used to verify the enhancement effect of each bases' contribution for the probe.4.In order to identify the low concentration of imidophos in the water environment,the characteristics of surface-enhanced Raman spectroscopy were studied.Firstly,the erythrosine solution was selected as a probe reagent to verify the stability of the substrate,and the nanosilver gel and the probe molecules can quickly reach the mutual adsorption state and remain stable in a short time.Sodium chloride was used as both a reference and the aggregating agent during the detection of the Imidophos solution.Every characteristic Raman band of the Iminophos was calculated and its corresponding vibrational bond position was analyzed combined with the density functional theory.Finally,the concentration of the different concentration of Imidophos solution was quantitatively predicted by back propagation artificial neural network. |
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