Infrared spectra Fourier transform

Figure 2.18 Fourier transform infrared spectrum of sol-gel film composed of three layers and containing 10% vancomycin after 14 days of immersion in phosphate-buffered saline (weight measurements and release study showed 90% weight loss and 80% release). Intense silica bands and the bands associated with vancomycin (centred at 1660,1500 and 1397 cm-1) suggest the presence of a sol-gel film with vancomycin that remains after 14 days of immersion. (Reproduced from ref. 13, with permission.)...

Figure 6. Subtractive Photoacoustic Fourier Transform Infrared Spectrum of Propylated Wyodak Coal.

The electronic and vibrational spectra of benzoquinones are very diagnostic. Of the two possible isomers remaining, the 2,5-substituted quinone (5) would be expected to give two different electronic transitions of equal intensity around 280 nm, and only one carbonyl stretching band. The Fourier transform infrared spectrum (CH2CI2) of the haustorial Inducer showed strong absorptions at 1698 (vC=0), 1646 (vC=0) and 1597 cm (vC=C). These spectroscopic data established the haustorial inducer as 2,6-diraethoxy-2"benzoquinone (2,6-DMBQ, 4). 

We conclude this chapter by presenting several examples of deconvolution of real data. Most of these examples represent deconvolutions of data that were used as part of a spectral analysis rather than generated as deconvolution examples or tests. The examples include high-resolution grating spectra, tunable-diode-laser (TDL) spectra, a Fourier transform infrared spectrum (FTIR), laser Raman spectra, and a high-resolution y-ray spectrum. 

Figure 20-29 Fourier transform infrared spectrum of polystyrene film. The Fourier transform of the background interferogram gives a spectrum determined by the source intensity, beamsplitter efficiency, detector response, and absorption by traces of H20 and C02 in the atmosphere. The sample compartment is purged with dry N2 to reduce the levels of H20 and C02. The transform of the sample interferogram is a measure of all the instrumental factors, plus absorption by the sample. The transmission spectrum is obtained by dividing the sample transform by the background transform.

C. Refer to the Fourier transform infrared spectrum in Figure 20-29. 

F. Stroh, M. Winnewisser, and B. P. Winnewisser, J. Mol. Spectrosc., 162,435 (1993).The High-Resolution Fourier Transform Infrared Spectrum of Isocyanogen, CNCN Rovibra-tional Analysis of the v4, v5, and v4+v5 Band Systems and the Fermi Dyad v3 and 2v4. 

Figure 22 Vibrational spectra of human stratum comeum. FTIR Fourier transform infrared spectrum FT-Raman Fourier transform Raman spectrum. (From Ref. 185. Reprinted from International Journal of Pharmaceutics, 81 (2-3), Williams et al. Fourier transform Raman spectroscopy A novel application for examining human stratum comeum, pp. R11-R14,1992, with kind permission from Elsevier Science, ML, Sara Burgerhartstraaat 25, 1055 KV, Amsterdam, The Netherlands.)...

Figure 3 - Fourier Transform - Infrared Spectrum of a Typical Silicone Gel.

Figure 9 Fourier Transform-Infrared Spectrum (FT-IR) of Silicone Extractables Fluids...

Noguchi T, Mitsuka T and Inoue Y (1994) Fourier transform infrared spectrum of the radical cation of 3-carotene photoinduced in Photosystem II. FEES Lett 356 I79-I82... 

Band Assignments.—The Fourier transform infrared spectrum of C-difluoro-phosphaethane has been analysed and the P=C band assigned. The Vps, band assignments for silylphosphines have been discussed. The positions of and Vp isNH are reported and used to characterize isomeric phosphine-iminium salts. The vpo (sym) bands of barium dialkyl phosphates have been compared in liquid crystal and aqueous media. ... 

Figure 2. Fourier transform infrared spectrum of pergolide mesylate... 

This method was in fact carried out around two decades ago [30, 31]. However, it was applied only in the fermentation of pure microbial cultures. In a recent report by Acros-Hernandez and coworkers [32], infrared spectroscopy was applied to quantify the PHA produced in microbial mixed cultures. Around 122 spectra from a wide range of production systems were collected and used for calibrating the partial least squares (PLS) model, which relates the spectra with the PHA content (0.03-0.58 w/w) and 3-hydroxyvalerate monomer (0-63 mol%). The calibration models were evaluated by the correlation between the predicted and measured PHA content (R ), root mean square error of calibration, root mean square error of cross validation and root mean square error of prediction (RMSEP). The results revealed that the robust PLS model, when coupled with the Fourier-Transform infrared spectrum, was found to be applicable to predict the PHA content in microbial mixed cultures, with a low RMSEP of 0.023 w/w. This is considered to be a reliable method and robust enough for use in the PHA biosynthesis process using mixed microbial cultures, which is far more complex. 

Spectral Database for Organic Compounds (SDBS) is an integrated spectral database system for organic compounds, which includes six different types of spectra, an electron-impact mass spectrum (EI-MS), a Fourier transform infrared spectrum (FT-IR), a H NMR spectrum, a NMR spectrum, a laser Raman spectrum, and an electron spin resonance (ESR) spectrum [72], SDBS is maintained by the National Metrology Institute of Japan (NMU) under the National Instimte of Advanced Industrial Science and technology (AIST). Currently, EI-MS spectrum, H NMR spectrum, C NMR spectrum, FT-IR spectrum, and the compound dictionary are... 

In several papers (Arvanitoyannis et al. 1997, Chuang et al. 1999, Koyano et al. 2000, Yang et al. 2004), however, the two polymers have been reported to be essentially immiscible. They reported the difficult compatibility by differential scanning calorimetry (DSC), scanning electron microscopy (SEM), Fourier transform infrared spectrum (FUR), electron-probe microanalyzer, etc. Among them, Koyano et al. (2000) pointed out that the chitosan content is dependent upon the position of the film and chitosan is concentrated on the air-surface side of the films. In another research, however, Arvanitoyannis et al. (1997) reported that the difficulty could be mitigated by adding sorbitol and sucrose as plasticizer. 

Figure 1.17 Attenuated total reflectance Fourier transform infrared spectrum of Compound 6, the carbon-black filled, vulcanised rubber compound containing the antiozonant. The arrow highlights the only peak visibly different from the ATR-IR spectrum of Compound 2, which does not contain the antiozonant...

Figure 3.5 shows the Fourier transform infrared spectrum of polymethylmethacrylate (PMMA). Figure 3.6 (top spectrum) shows a spectrum of an acrylonitrile-butadiene copolymer of unknown composition. The lower spectrum is a match obtained from one of a range of standard copolymers of known composition demonstrating that the unknown copolymer contains between 30 and 32% acrylonitrile and between 70 and 68% butadiene. 

Figure 7.3 Chemical characterization of chitosan-nH A. (a) Fourier Transform-Infrared Spectrum (FT-IR). (b) X-ray diffraction spectrum (c) transmission images of nHA and chitosan-nHA.

The Fourier transform infrared spectrum (FITR) of (II) shows absorptions both from the organic and FeOCI portions of the material. The presence of polyfuran in (II) is apparent when comparing its FITR spectrum with that of chemically prepared bulk polyfuran and that of polyfuran extracted firom(n). This is shown in Figure 5. 

---