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Extended analysis of FTIR high resolution spectra of HD32S and HD34S in the region of the ν2 band: Positions and strengths of individual lines
摘要： The high resolution infrared spectra of deuterated hydrogen sulfide HDS were recorded with a Bruker IFS125HR Fourier transform infrared spectrometer (Zurich prototype ZP2001) and analyzed in the ν2 fundamental band region, 690–1510 cm?1. 2684 transitions with maximum values of the quantum numbers Jmax.=25 and Kmax.a=17 were assigned in the experimental spectra to the ν2 band (compared to Jmax.=22 and Kmax.a=10 in the preceding analogous studies) of HD32S. On this basis, 415 upper ro–vibrational energies were obtained, which were used then in the weighted fit of the Watson Hamiltonian parameters. 33 parameters obtained from the fit reproduce the 415 initial energy values with a root mean square deviation drms=1.1×10?? cm?1. An analysis of 418 experimental ro–vibrational line intensities of the ν2 band of HD32S was made using the Hartmann–Tran profile of individual lines, and results were applied in the fit of parameters of the effective dipole moment operator. Isotopic relations for the dipole moment parameters were derived and used for the fit procedure. The obtained 'model' parameters reproduce the initial line strengths with the drms=4.7%. A list of 2684 experimental transitions of HDS is generated together with the presentation of their individual line strengths predicted on the basis of the obtained effective dipole moment parameters. An analogous analysis was fulfilled for the ν2 band of the HD3?S isotopologue.
关键词： HD32S,isotopic substitution,FTIR,ν2 band,line positions,HD34S,high resolution spectra,line strengths,spectroscopic parameters
更新于2025-09-23 15:23:52
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A new metal-organic hybrid crystal with excellent transparency in the visible spectrum: Growth, structure and properties of sodium fumarate – Boric acid tetrahydrate
摘要： Single crystals of sodium fumarate-boric acid tetrahydrate (SBF) were grown by a slow evaporation solution technique. The crystal belongs to orthorhombic lattice system. Identification of the functional groups and the nature of bonding involved in this crystal were elucidated by FTIR. The crystal is transparent in the entire visible region with a lower cutoff around 384 nm and the band gap of 5.5 eV. The photoactive material can have the ability to emit fluorescent radiation in the wavelength range of 490 nm. The hydrated crystal is thermally stable; in the receipt of dehydration it loses its stability. The mechanically soft natured crystal obeys the reverse indentation size effect for the applied loads. The elevated dielectric constant and dielectric loss are assisted by the hydrated water and it diminished as the material dehydrates at higher temperature. The slower motion of the dipole induces frequency of the applied field and hence the impedance decreases with increasing frequency.
关键词： soft nature,FTIR,Fluorescent,RISE
更新于2025-09-23 15:23:52
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Determination of liquid egg composition using ATR-FTIR spectroscopy and chemometrics
摘要： BACKGROUND: The use of liquid whole egg (LWE) in food industry as a substitute for shell eggs has been on the increase lately. Since the composition of LWE can easily be changed, determination of protein, lipid, moisture, and total soluble solid (TSS) contents of LWE has also gained importance. Traditional methods usually require more time and effort, and the use of toxic chemicals for sample preparation, where more efficient techniques (faster, cheaper, and more reliable) are needed. In this concern, a novel technique that determines LWE components using ATR-FTIR spectroscopy with partial least square regression (PLS) is presented in this study. RESULTS: The actual values of LWE components were detected by applying reference methods. The accuracy of PLS model was demonstrated by comparing the obtained predictions with the actual values of the component. High coefficients of determination values, which are 0.950, 0.992, 0.994, and 0.972, were achieved for protein, lipid, moisture, and TSS validation data sets, respectively. The error values, namely RMSEC, RMSECV, and RMSEP, were obtained in the range of 0.404-0.978, 0.57-1.82, and 0.83-1.84, respectively. CONCLUSION: ATR-FTIR spectroscopy coupled with chemometrics can provide a rapid and sensitive method for quality control of liquid egg composition.
关键词： chemometrics,composition,Liquid whole egg,ATR-FTIR spectroscopy,reference method
更新于2025-09-23 15:23:52
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Silver Nanostructures on Graphene Oxide as the Substrate for Surface-Enhanced Raman Scattering (SERS)
摘要： Nanosized surface-enhanced Raman scattering (SERS) substrates fabricated by the controlled growth of metal nanostructures on water-dispersed two-dimensional nanomaterials can open a new avenue for SERS analysis of liquid samples in biological fields. In this work, regular and uniform Ag nanostructures were grown on the surface of graphene oxide (GO) through a microwave-assisted hydrothermal method. Polyamidoamine (PAMAM) dendrimers were assembled on the surface of GO to form GO/PAMAM templates for growing Ag nanostructures, which are primarily comprised of Ag dimers and trimers. The prepared Ag/GO nanocomposites are highly dispersed and stable in aqueous solution and may be used as substrates for enhanced Raman detection of rhodamine 6 G (R6G) in aqueous solution. This special substrate provides high-performance SERS and suppresses R6G fluorescence in aqueous solution and is promising as a nanosized material for the enhanced Raman detection of liquid samples in biological diagnostics.
关键词： graphene oxide (GO),Surface-enhanced Raman scattering (SERS),polyamidoamine (PAMAM) dendrimers,transmission electron microscopy (TEM),Fourier transform infrared (FTIR) spectroscopy,rhodamine 6G (R6G)
更新于2025-09-23 15:23:52
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Vibrational characterization of granulosa cells from patients affected by unilateral ovarian endometriosis: New insights from infrared and Raman microspectroscopy
摘要： Endometriosis is a chronic gynaecological disease characterised by the presence of endometrial cells in extra-uterine regions. One of the main factors impacting on the fertility of women affected by endometriosis is the poor oocyte quality. Granulosa Cells (GCs) regulate oocyte development and maintain the appropriate microenvironment for the acquisition of its competence; hence, the dysregulation of these functions in GCs can lead to severe cellular damages also in oocytes. In this study, luteinized GCs samples were separately collected from both ovaries of women affected by Unilateral Ovarian Endometriosis and analyzed by infrared and Raman microspectroscopy. The spectral data were compared with those of GCs from women with diagnosis of tubal, idiopathic or male infertility (taken as control group). The coupling of these two spectroscopic techniques sheds new light on the alteration induced by this pathology on GCs metabolism and biochemical composition. In fact, the study revealed similar biochemical modifications in GCs from both ovaries of women affected by unilateral ovarian endometriosis, such as the alteration of the protein pattern, the induction of oxidative stress mechanisms, and the deregulation of lipid and carbohydrate metabolisms. These evidences suggest that unilateral endometriosis impairs the overall ovarian functions, causing alterations not only in the ovary with endometriotic lesions but also in the contralateral “healthy” one.
关键词： Unilateral Ovarian Endometriosis,Multivariate analysis,FTIR microspectroscopy,Raman microspectroscopy
更新于2025-09-23 15:23:52
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Prediction of coumarin and ethyl vanillin in pure vanilla extracts using MID-FTIR spectroscopy and chemometrics
摘要： Fourier transform mid-infrared (MID-FTIR) spectroscopy coupled with chemometric analysis was used to identify and quantify coumarin (CMR) and ethyl vanillin (EVA) adulterations in pure vanilla extracts. Forty samples adulterated with CMR (0.25-10 ppm) and forty with EVA (0.25-10%) were prepared from pure vanilla extracts and characterized by MID-FTIR spectroscopy to develop chemometric models. Additionally, six commercial vanilla samples were analyzed. A soft independent modeling of class analogy (SIMCA) model was developed to identify and classify the purity from EVA-adulterated or CMR-adulterated samples. Prediction models for CMR or EVA content were developed using the principal component regression (PCR), partial least squares with single y-variables (PLS1), and with multiple y-variables (PLS2) algorithms. Moreover, the predictions of the best quantification chemometric model were compared with the results of a high-performance liquid chromatography-diode array detector (HPLC-DAD) method to evaluate the accuracy of the prediction. The PLS1 algorithm had better performance using 3 and 8 factors for EVA and CMR, respectively. The SIMCA model showed 100% recognition and rejections rates. The results demonstrate that adulteration of pure vanilla with EVA and CMR could be successfully predicted by the developed technique.
关键词： coumarin,ethyl vanillin,chemometrics,MID-FTIR,vanilla extracts,adulteration
更新于2025-09-23 15:23:52
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The Influence of Instrumental Line Shape Degradation on the Partial Columns of O3, CO,CH4 and N2O Derived from High-Resolution FTIR spectrometry
摘要： High resolution Fourier transform infrared (FTIR) measurement of direct sunlight does not only provide information of trace gas total columns, but also vertical distribution. Measured O3, CO, CH4, and N2O can be separated into multiple partial columns using the optimal estimation method (OEM). The retrieval of trace gas profiles is sensitive to the instrument line shape (ILS) of the FTIR spectrometer. In this paper, we present an investigation of the influence of ILS degradation on the partial column retrieval of O3, CO, CH4, and N2O. Sensitivities of the partial column, error, and degrees of freedom (DOFs) of each layer to different levels of ILS degradation for O3, CO, CH4, and N2O are estimated. We then evaluate the impact of ILS degradation on the long-term measurements. In addition, we derive the range of ILS degradation corresponding to the acceptable uncertainties of O3, CO, CH4, and N2O results. The results show that the uncertainties induced by the ILS degradation on the absolute value, error, and the DOFs of the partial column are altitude and gas species dependent. The uncertainties of the partial columns of O3 and CO are larger than those on CH4 and N2O. The stratospheric partial columns are more sensitive to the ILS degradation compared to the tropospheric part. Our result improves the understanding of the ILS degradation on the FTIR measurements, which is important for the quantification of the measurement uncertainties and minimizes the bias of the inter-comparison between different measurement platforms. This is especially useful for the validation of satellite observations, the data assimilation of chemical model simulations, and the quantification of the source/sink/trend from the FTIR measurements.
关键词： partial column,instrument line shape,FTIR,NDACC
更新于2025-09-23 15:23:52
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AIP Conference Proceedings [Author(s) 1ST INTERNATIONAL CONGRESS ON SOLAR ENERGY RESEARCH, TECHNOLOGY AND APPLICATIONS (ICSERTA 2018) - Ouarzazate, Morocco (8–10 May 2018)] - Synthesis and MID-IR characterization of strontium hexaferrite nanoparticles using gel to crystallization technique
摘要： Synthesis and MID-IR characterization of strontium hexaferrite nanoparticles using gel to crystallization technique. Strontium hexaferrite (SrFe12O19) nanoparticles have been synthesized using gel to crystallization technique. Citric acid, iron nitrate and strontium nitrate were used as starting materials to prepare the gel. The prepared gel was heated at 100°C for 4 hrs in muffle furnace and sample was annealed at 800°C for 4 hrs. The prepared sample was characterized by X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. The XRD pattern confirms the formation of single phase SrFe12O19 nanoparticles. The FTIR spectrum shows the absorption bands in the range 400-600 cm-1 which are assigned to metal-oxygen vibrations. The prepared nanoparticles show the formation of single phase and can be used for various applications such as magnetic recording media, microwave devices and permanent magnets.
关键词： XRD,FTIR,gel to crystallization,Strontium hexaferrite,nanoparticles
更新于2025-09-23 15:23:52
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Rapid Quantitative Analysis of Forest Biomass Using Fourier Transform Infrared Spectroscopy and Partial Least Squares Regression
摘要： Fourier transform infrared reflectance (FTIR) spectroscopy has been used to predict properties of forest logging residue, a very heterogeneous feedstock material. Properties studied included the chemical composition, thermal reactivity, and energy content. The ability to rapidly determine these properties is vital in the optimization of conversion technologies for the successful commercialization of biobased products. Partial least squares regression of first derivative treated FTIR spectra had good correlations with the conventionally measured properties. For the chemical composition, constructed models generally did a better job of predicting the extractives and lignin content than the carbohydrates. In predicting the thermochemical properties, models for volatile matter and fixed carbon performed very well (i.e., R2 > 0.80, RPD > 2.0). The effect of reducing the wavenumber range to the fingerprint region for PLS modeling and the relationship between the chemical composition and higher heating value of logging residue were also explored. This study is new and different in that it is the first to use FTIR spectroscopy to quantitatively analyze forest logging residue, an abundant resource that can be used as a feedstock in the emerging low carbon economy. Furthermore, it provides a complete and systematic characterization of this heterogeneous raw material.
关键词： FTIR spectroscopy,forest logging residue,energy content,partial least squares regression,thermal reactivity,chemical composition
更新于2025-09-23 15:22:29
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Improved Photocatalytic Properties of NiS Nanocomposites Prepared by Displacement Method for Removal of Rose Bengal Dye
摘要： Objective: The present work describes NiS nanoparticles were prepared by chemical displacement method using CTAB as a stabilizer. Method: For the source of Sulfide ion, we used thioacetamide as fuel and nickel nitrate as metal salt. NiS nanoparticles are p-type semiconductor. Band gap of NiS is 0.5- 0.6 eV and also reported to be a good photo catalyst in the degradation of pollutants. The structural, morphological, metal percentage and optical properties of as synthesized nanoparticles are investigated by using X-ray diffraction (XRD), UV-Visible spectra; Field emission gun scanning electron microscopy (FEG-SEM) with EDS, Fourier transforms infrared spectroscopy (FTIR), High-resolution transmission electron microscopy (HR-TEM) and Photoluminescence spectroscopy (PL). Results: The x-ray diffraction patterns revealed that the particles exhibited a crystal structure at the suitable temperature. The average particle size of the nanoparticles from the X-ray diffraction is about 22.8 nm and also Field emission gun scanning electron microscopy shows good morphology and exhibited clearly hexagonal shape. Conclusion: The Transmission electron microscopy (HR-TEM) shows the crystalline size of structures is 22 nm. Further, the Photocatalytic activity of Synthesized NiS nanoparticles was investigated by photo catalytic removal of Rose Bengal as a model of organic pollutant. It shows good photocatalytic activity against Rose Bengal dye (98.1%).
关键词： Nanoparticles,UV-Vis,FEG-SEM,EDAX,XRD,FTIR,HR-TEM,nickel sulfide
更新于2025-09-23 15:22:29