Pyrolysis-Fourier Transform Infrared Spectroscopy

Modem PyFTlR equipment allows thermal evolution, vaporisation and pyrolysis directly in the FTTR. In direct PyFTIR the sample is located 3 mm below the beam [833,834]. Washall et al. [833] have described a cylindrical interface equipped with KBr windows, for connection of a ribbon filament pyrolyser to FTIR. Also sample cells with ZnSe windows are available for insertion into the light path of a Fourier transform infrared spectrometer for direct FTTR measurement of intricate solids. 

Library search requires gas phase spectral databases (e.g. NIH/EPA) and archived spectra. For identification purposes temperature-programmed PyFTIR with appropriate data processing (differentiation, profile subtraction, etc.) has been used [835]. 

Advantages of pyrolysis directly in the IR beam are that spectra are obtained before side reactions and condensation occur. Direct PyFTIR provides a cleaner, simpler method for polymer analysis and also eliminates the need to transfer the gas phase sample to the IR sampling compartment, resulting in less dilution, analysis of smaller samples, and the possibility of monitoring the earliest species. 

Although FTIR can readily be utilised for the analysis of pyrolysates, and has some advantages over PyMS and TVA, a disadvantage of PyFTIR is the lower sensitivity relative to mass spectrometry. This explains the limited usage of this complementary technique. The sensitivity of pyrolysis-IR spectroscopy is surpassed by pyrolysis-laser photoacoustic spectroscopy, a combination of filament pyrolysis and CO2 laser photoacoustic detection [838]. 

Reviews dealing with pyrolysis as a sampling technique for IR spectroscopy and for the determination of the microstructure of synthetic polymers are few and dated [557,561,839,840]. In a standard treatise on qualitative and quantitative analysis of rubbers and elastomers (Bayer technology, 1981) Ostromow [260] ranks off-line PylR still amongst the main techniques utilised. 

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Fourier transform infrared spectroscopy nuclear meagnetic resonance Electron Spin Resonance Pyrolysis-gas chromatography Pyrolysis-mass spectrometry Pyrolysis-Fourier transform infrared spectroscopy pH titration Binding Studies... 

Washall, J.W. Wampler, T.P. Direct-pyrolysis Fourier transform-infrared spectroscopy for polymer analysis. Spectroscopy 1992, 6 (4), 38. 

If a simple qualitative identification of a plastic is all that is required then fingerprinting techniques discussed in Chapter 6 may suffice. Fingerprinting instrumentation discussed include glass transition, pyrolysis techniques, infrared spectroscopy, pyrolysis - Fourier transform infrared spectroscopy, Raman spectroscopy and radio frequency slow discharge mass spectrometry. 

PyFTIR Pyrolysis-Fourier transform infrared RS Raman scattering/spectroscopy... 

Goodacre, R. Shann, B. Gilbert, R. J. Timmis, E. M. McGovern, A. C. Alsberg, B. K. Kell, D. B. Logan, N. A. Detection of the dipicolinic acid biomarker in Bacillus spores using Curie-point pyrolysis mass spectrometry and fourier transform infrared spectroscopy Anal. Chem. 2000,72,119-127. 

McGovern, A. C. Ernill, R. Kara, B. V. Kell, D. B. Goodacre, R. Rapid analysis of the expression of heterologous proteins in Escherichia coli using pyrolysis mass spectrometry and Fourier transform infrared spectroscopy with chemometrics Application to a2- interferon production. J. Biotechnol. 1999, 72,157-167. 

Timmins, E. M. Howell, S. A. Alsberg, B. K. Noble, W. C. Goodacre, R. Rapid differentiation of closely related Candida species and strains by pyrolysis mass spectrometry and Fourier transform infrared spectroscopy. /. Clin. Microbiol. 1998,36, 367-374. 

V.A. Basiuk, Pyrolysis of valine and leucine at 500°C identification of less volatile products using gas chromatography Fourier Transform infrared spectroscopy mass spectrometry, J. 

The flame retardant mechanism of PC/ABS compositions using bisphenol A bis(diphenyl phosphate) (BDP) and zinc borate have been investigated (54). BDP affects the decomposition of PC/ABS and acts as a flame retardant in both the gas and the condensed phase. The pyrolysis was studied by thermogravimetry coupled with fourier transform infrared spectroscopy (FUR) and nuclear magnetic-resonance spectroscopy. Zinc borate effects an additional hydrolysis of the PC and contributes to a borate network on the residue. 

Usami, T., Itih, T., Ohtani, H., Tsuge, S. (1990) Structural study of polyacrylonitrile libers during oxidative thermal degradation by pyrolysis-gas chromatography, solid state 13C Nuclear magnetic resonance and Fourier transform infrared spectroscopy, Macromolecules 23, 2460-2465. 

Pakdel H, Grandmaison JL, Roy C (1989) Analysis of wood vacuum pyrolysis solid residues by diffuse reflectance infrared Fourier transform spectrometry Can J Chem 67 310-314 Perkins WD (1986) Fourier transform-infrared spectroscopy Part I Instrumentation J Chem Educ 63 A5-A10... 

Fourier transform infrared spectroscopy (FTIR) was also used to monitor the degree of pyrolysis for various samples at different temperatures. The KBr (potassium bromide) pellet of sample was prepared for FTIR analysis. 

Marshall C. P., Wilson M. A., Hartung-Kagi B., and Hart G. (2001) Potential of emission Fourier transform infrared spectroscopy for in situ evaluation of kerogen in source rocks during pyrolysis. Chem. Geol. 175, 623-633. 

Conversion of the as-deposited film into the crystalline state has been carried out by a variety of methods. The most typical approach is a two-step heat treatment process involving separate low-temperature pyrolysis ( 300 to 350°C) and high-temperature ( 550 to 750°C) crystallization anneals. The times and temperatures utilized depend upon precursor chemistry, film composition, and layer thickness. At the laboratory scale, the pyrolysis step is most often carried out by simply placing the film on a hot plate that has been preset to the desired temperature. Nearly always, pyrolysis conditions are chosen based on the thermal decomposition behavior of powders derived from the same solution chemistry. Thermal gravimetric analysis (TGA) is normally employed for these studies, and while this approach seems less than ideal, it has proved reasonably effective. A few investigators have studied organic pyrolysis in thin films by Fourier transform infrared spectroscopy (FTIR) using reflectance techniques. - This approach allows for an in situ determination of film pyrolysis behavior. 

Fourier transform infrared spectroscopy Fourier transform mass spectrometry Fourier transform nuclear magnetic resonance fusion (melting) flash vacuum pyrolysis full width at half maximum... 

Additionally, a variety of analytical equipment and techniques that allow the examination of small- (and micro-) scale microbial cultures and their products have become available. Examples include near infrared and Fourier transform infrared spectroscopy, which offer the ability for in situ detection of specific compounds in fermentation broth [22]. However, sensitivity and the required sample volumes pose serious obstacles that still have to be overcome. Another alternative is offered by sensitive pyrolysis mass spectroscopy, which was demonstrated to be suitable for quantitative analysis of antibiotics in 5-pl aUquots of fermentation broth when combined with multivariate calibration and artificial neural networks [91]. The authors concluded that a throughput of about 12,000 isolates per month could be expected. Furthermore, standard chromatographic methods such as gas chromatography or high-performance liquid chromatography, possibly in combination with mass spectroscopy (MS) for detection, can provide simultaneous quantitative detection of many metabolic products. 

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