Pyrolysis - mass spectrometry technique

Price and workers [31] studied the flame retardancy of rigid PU foams with various isocyanate indexes using the laser pyrolysis-mass spectrometry technique. 

Huai, H., Lo, R., Yun, Y, Meuzelaar, H.L.C. (1990) A comparative study of eight US coals by several different pyrolysis mass spectrometry techniques. ACS Preprints, Division of Fuel Chemistry, 35,816-823. 

With recent developments in analytical instrumentation these criteria are being increasingly fulfilled by physicochemical spectroscopic approaches, often referred to as whole-organism fingerprinting methods.910 Such methods involve the concurrent measurement of large numbers of spectral characters that together reflect the overall cell composition. Examples of the most popular methods used in the 20th century include pyrolysis mass spectrometry (PyMS),11,12 Fourier transform-infrared spectrometry (FT-IR), and UV resonance Raman spectroscopy.16,17 The PyMS technique... 

Meuzelaar, H. L. Kistemaker, P. G. A technique for fast and reproducible fingerprinting of bacteria by pyrolysis mass spectrometry. Anal. Chem. 1973, 45, 587-590. 

X. Zang, J.C. Brown, J.D.H. van Heemst, A. Palumbo, P.G. Hatcher, Characterization of Amino Acids and Proteinaceous Materials using Online Tetramethylammonium Hydroxide (TMAH) Thermochemolysis and Gas Chromatography Mass Spectrometry Technique, Journal of Analytical and Applied Pyrolysis, 61, 181 193 (2001). 

McGovern et al.26 analyzed the expression of heterologous proteins in E. coli via pyrolysis mass spectrometry and FT-IR. The application was to a2-interferon production. To analyze the data, artificial neural networks (ANN) and PLS were utilized. Because cell pastes contain more mass than the supernatant, these were used for quantitative analyses. Both the MS and IR data were difficult to interpret, but the chemometrics used allowed researchers to gain some knowledge of the process. The authors show graphics indicating the ability to follow production via either technique. 

Qian, K. Killinger, W.E. Casey, M. Nicol, G.R. Rapid Polymer Identification by In-Source Direct Pyrolysis Mass Spectrometry and Library Searching Techniques. Anal. Chem. 1996, 68, 1019-1027. 

Many of the compositional parameters utilized as independent variables in the work cited above represented derived coal properties rather than fundamental chemical features. Further, variables traditionally used are often highly correlated with each other (for example volatile matter and hydrogen). As pointed out by Neavel (34) / this limits the utility of such parameters in correlational models. Instrumental techniques such as pyrolysis/mass spectrometry (35.36 C-n.m.r, FTIR, and... 

Another rapid technique for characterizing non-volatile materials which has been applied to coal macerals is pyrolysis mass spectrometry (Py-MS) (82-84). The evaluation of the complex data produced by this technique has been aided by the use of statistical analysis. Homologous series of molecules can be identified and variation between the various maceral groups is quite evident. 

Pyrolysis-Gas Chromatography-Mass Spectrometry Techniques for Poly Studies... 

In pyrolysis-mass spectrometry (Py-MS) the pyrolysate is directly transferred to a mass spectrometer and analyzed, generating a complex spectrum. The sample introduction can be done using various techniques. One simple technique is the direct insertion probe (DIP) where the sample is deposited on an insert that has the capability of heating the sample and of introducing the pyrolysate directly into the ion source of the mass spectrometer (see e.g. [1]). Another technique is the Curie point Py-MS where an attachment to the mass spectrometer allows the sample to be placed in a radio frequency (RF) region continued by an expansion chamber connected to the ion source. The sample is pyrolyzed and the pyrolysate ionized and analyzed in the MS instrument. A schematic diagram of a Curie point Py-MS system is shown in Figure 3.3.2. 

Anklam, E., Lipp, M., Radovic, B., Chiavaro, E., and Palla, G. Characterisation of Italian vineear by pyrolysis-mass spectrometry and a sensor technique. Food Chem., 61, 243,1998. 

The true value of analytical pyrolysis for the characterization of organic matter is realized when combined with analytical methods such as mass spectrometry (Pyrolysis-Mass Spectrometry, Py-MS). High sensitivity, specific and fast analysis are widely recognized characteristics of mass spectrometry (MS), which have earned this technique its reputation as one of the most powerful analytical tools for organic materials available today. With the total number of library mass spectra... 

The low volatility of macromolecules initially precluded the widespread application of MS analysis to polymer systems. Nevertheless, meaningful structural information can be extracted from the mass spectra of unvolatile macromolecules by El, Cl, and FI techniques, and this is due to the considerable attention that has been focused on the methods of characterization of polymers by Direct Pyrolysis Mass Spectrometry (UPMS). " ... 

The application of pyrolysis techniques to the study of forensic samples has a long and well-documented history, including a review of pyrolysis-mass spectrometry as a forensic tool in 1977 by Saferstein and Manura, and a general review by Wheals. A wide variety of sample types have been investigated, including chewing gum, rubber and plastic parts from automobiles, drugs, and blood stains. 

Pyrolysis Mass Spectrometry Instrumentation, Techniques, and Applications... 

Pyrolysis-mass spectrometry (Py-MS) has found many applications in microbiology, geochemistry, and soil and polymer sciences. However, its development has been historically hindered by the lack of competitively priced instrumentation, which has restricted the number of laboratories able to use the technique. Furthermore, because of the nature and complexity of the data produced, a heavy reliance upon statistical techniques has been required for data analysis. This specific problem has benefited greatly from the development of powerful personal computers and the increased availability of suitable software, as well as the reduction in price of mass spectrometers and the production of specific libraries for pyrolysis work. 

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