The Fourier Transform infrared

Carbon monoxide and carbon dioxide can be measured using the FTIR techniques (Fourier transform infrared techniques see the later section on the Fourier transform infrared analyzer). Electrochemical cells have also been used to measure CO, and miniaturized optical sensors are available for CO 2 monitoring. 

Xiao H-K, Levine SP, D Arcy JB, et al. 1990. Comparison of the Fourier transform infrared (FTIR) spectrophotometer and the Miniature Infrared Analyzer (MIRAN ) for the determination of trichloroethylene (TCE) in the presence of Freon -113 in workplace air. Am Ind Hyg Assoc J 51 395-401. 

F.C. Strong III, How the Fourier transform infrared spectrophotometer works. J. Chem. Educ., 56(1979) 681-684. 

Recently, nonliving biomass of S. cucullata has been described as a low-cost absorbent of Cr(VI).106 Optimum conditions for the Cr(VI) adsorption by acid-treated S. cucullata were found out using a full factorial design. The Cr(VI) removal efficiency of the adsorbent was found to increase with the increase in time, temperature, adsorbate concentration, and stirring speed, and to decrease with increase in pH and adsorbent dose. The Fourier transform infrared spectroscopy (FT-IR) analysis revealed that in addition to electrostatic force, the adsorption may be due to... 

Computational methods were employed to predict molecular vibrations in 3-mercato-l,2,4-triazole 18 and 3,5-diamino-1,2,4-triazole 19 in order to fully assign the Fourier transform infrared (FTIR) and FT-Raman spectra of these molecules <2004SAA709, 2005SAA261>. 

We discussed the fundamentals of mass spectrometry in Chapter 10 and infrared spectrometry in Chapter 8. The quadrupole mass spectrometer and the Fourier transform infrared spectrometer have been adapted to and used with GC equipment as detectors with great success. Gas chromatography-mass spectrometry (GC-MS) and gas chromatography-infrared spectrometry (GC-IR) are very powerful tools for qualitative analysis in GC because not only do they give retention time information, but, due to their inherent speed, they are also able to measure and record the mass spectrum or infrared (IR) spectrum of the individual sample components as they elute from the GC column. It is like taking a photograph of each component as it elutes. See Figure 12.14. Coupled with the computer banks of mass and IR spectra, a component s identity is an easy chore for such a detector. It seems the only real... 

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). 

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

For qualitative analysis, two detectors that can identify compounds are the mass spectrometer (Section 22-4) and the Fourier transform infrared spectrometer (Section 20-5). A peak can be identified by comparing its spectrum with a library of spectra recorded in a computer. For mass spectral identification, sometimes two prominent peaks are selected in the electron ionization spectrum. The quantitation ion is used for quantitative analysis. The confinnation ion is used for qualitative identification. For example, the confirmation ion might be expected to be 65% as abundant as the quantitation ion. If the observed abundance is not close to 65%, then we suspect that the compound is misidentified. 

The samples of free lipase, pure silica (PS), silanized and activated silica, and immobilized derivatives were submitted to the Fourier Transform Infrared Spectroscopy (FTIR) analysis (Spectrophotometer FTIR BOMEM MB-100). The spectra were obtained in the wavelength range of 400-4000 cm-1 for evaluation of the immobilization procedures. 

Diffuse Reflectance, Attenuated Total Reflection or Multiple Internal Reflection, Photoacoustic (PAS), Photothemal Beam Deflection, Specular Reflection Absorption, and forensic applications with the diamond cell and the Fourier transform infrared (FTIR) microscope. In museum laboratories, FTIR applications have been used for problems of identification and degradation in art and archeology. (14)... 

J.M. Bowen et al., Comparison of sample preparation methods for the Fourier transform infrared analysis of an organo-clay mineral sorption mechanism. Anal. Chem. 61, 2047-2050 (1989)... 

Cvi is the number of vinyl groups per chain. The direct observation of the decrease in amplitude of the Fourier Transform-Infrared spectroscopy (FT-IR) spectrum of vinyl groups leads to a square root dependence of a(t) on time. The threshold of gelation occurs at a time t0 such that e(t0) is equal to zero. Again, the magnetic relaxation rate is a function of the variable, e (Figure 8.4). 

Huvenne and Lacroix described a mathematical procedure for the correlation of band intensities of the Fourier-transform infrared absorption spectra with those of the corresponding infrared transmission spectra of compounds in KBr discs [22]. The procedure was applied to spectra of flunitrazepam, dipyridamole, and lactose that were obtained through the use of a Nicolet 7199 B FTIR spectrometer with photoacoustic detection. When the photoacoustic spectrum of a plant charcoal was used to correct the spectra for inequalities in the incident light flux before applying the procedure, the correlated band intensities were generally consistent with those obtained using infrared transmission spectra. The procedure may be useful for the direct identification of the drugs. 

Basically, in general PM-IRRAS experiment on any sample with polarized reflectances Rp and Rs, the signal at the detector output can be electronically split into a first part carrying only the intensity modulation induced by the moving mirror of the Fourier transform infrared (FTIR) spectrometer ... 

This procedure is equivalent to the Savitsky-Golay method, algorithms for which have been included in computer software for scientific instruments such as the Fourier-transform infrared (FTIR) spectrometer. Alternatives to smoothing are weighted least-squares fitting or optimal (Weiner) filtering techniques. ... 

The Fourier-transform infrared (FT-IR) spectra of a-and p-chitm are shown in Fig. 2.15. For a-chitin, the amide I band is split at about 1650 and 1620 cm (Fig. 2.15A), whereas it is a single sharp band at about 1657 cm for 3-chitin (Fig. 2.15B). The amide II band appears at about 1555 and 1559 cm for a- and (3-chitin, respectively. Both polymorphs show strong absorption bands in the 3100-3285 cm region which corresponds to the N-H group. The bands in the 2840-2960 cm region are due to CH, CH2, and CH3 in both chitin polymorphs. The FT-IR vibrational modes of a- and (3-chitins are summarized in Table 2.8. 

The Fourier transform infrared (FT-IR) spectrum (MB 147, BOMEM Canada) of magnesium silicate is shown in Fig. 7.11. The broad band between 3000 and 3700 cm is assigned to the fundamental stretching... 

The Fourier transform infrared spectroscopy (FTIR) spectra in Figure 7.15 are for BT-08 before and after chemical treatment for different durations. The... 

The infrared-electrochemical cell, originally designed by Bewick and his coworkers, was partly modified to introduce an electrode from the upper part of the cell. The front side of the cell is attached with a CaFg optical window, and the backside with a glass syringe which pushes the electrode against the window. The Fourier transform infrared measurements were conducted at 0 °C for Cu electrodes and at ambient temperature for Ni and Fe electrodes by JIR-6000 (Nihon Densi, Co. Ltd.) externally equipped with an MCT (mercury-cadmium-telluride) detector. Infrared spectra were acquired by the subtraction of two spectra reflected from the electrode at different potentials (SNIFTIRS). The other details were described previously. [9]... 

C. C., Huang, S.C. and Tsai, Y.H. (2003) Characterization of human cervical precancerous tissue through the Fourier transform infrared microscopy with mapping method. Gynecol. Oncol., 91, 577-83. 

Another example, but for spectroscopic data, is found in Gaetano et al. (54), who applied SVM on the Fourier-transform infrared spectra of olive oils in order to classify them according to geographical region. SVM performed... 

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