Pyrolysis mass spectroscopy

In this study, we extend the range of inorganic materials produced from polymeric precursors to include copper composites. Soluble complexes between poly(2-vinylpyridine) (P2VPy) and cupric chloride were prepared in a mixed solvent of 95% methanol 5% water. Pyrolysis of the isolated complexes results in the formation of carbonaceous composites of copper. The decomposition mechanism of the complexes was studied by optical, infrared, x-ray photoelectron and pyrolysis mass spectroscopy as well as thermogravimetric analysis and magnetic susceptibility measurements. 

Pyrolysis mass spectroscopy was conducted with a Hewlett-Packard model 5985B gas chromatograph/quadrupole mass spectrometer, operated at sslO- Torr and 70eV electron-impact ionization energy. Samples were introduced into the mass spectrometer via a glass lined direct insertion probe (DIP). The samples were decomposed in the DIP to a nominal temperature of 300°C at a heating rate of 30°C/min. 

Corkill, I Sisson, P. R. Smyth, A. Deveney, J. Freeman, R. Shears, P. Heaf, D. Hart, C. A. Application of pyrolysis mass spectroscopy and SDS-PAGE in the study of the epidemiology of Pseudomonas cepacia in cystic fibrosis. I. Med. Microbiol. 1994, 41,106-111. 

Figure 5.10 is the dynamic TGA scan of neat PTFE in air and N2. Under each atmosphere studied, it is readily apparent that the onset of degradation occurs at about 500°C. TGA data are also in excellent agreement with a more sensitive and structurally informative pyrolysis/mass spectroscopy analysis. Figure 5.11 is a... 

Boon, J. J., 1989, An introduction to pyrolysis mass spectroscopy of lignocellulosic material case studis of barley straw, com stem and Agropyron, in Physico-chemical Characterisation of Plant Residues for Industrial and Feed Use, A. Chesson, and E. R. 0rskov, eds., Elsevier Applied Science London, pp. 25-49. 

Flow Cytometry Pyrolysis Mass Spectroscopy Enzyme activities by specific analysis or mRNA blot... 

NADH by fluorescence Raman (Micro-) Spectroscopy Infrared Spectroscopy Pyrolysis Mass Spectroscopy NMR spectroscopy Lipid pattern by GC Some Small key metabolites Some enzyme activities Stress markers by electrophoresis or mRNA blot Small key metabolites... 

Even more recently, Burmester reported on the use of pyrolysis mass spectroscopy in lacquer studies (47,48). The results, when used with multivariate data analysis, prove to be a helpful provenance tool. Burmester has also extended the IR work through the use of a Fourier transform instrument and, further, evaluated the efficacy of using carbon-13 NMR measurements (49). 

Meuzelaar, H. L. C., Haverkamp, J., and Hileman, F. D., Pyrolysis Mass Spectroscopy of Recent and Fossil Biomaterials, Compendium and Atlas, 3rd ed., Elsevier Scientific Publishing Company, Amsterdam, 1991. 

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. 

The reason this method is so attractive to pyrolysis-mass spectroscopy (Py-MS) data is that it has been shown mathematically that a neural network consisting of only one hidden layer, with an arbitrary large number of nodes, can learn any arbitrary (and hence nonlinear) mapping to an arbitrary degree of accuracy. ANNs are also considered to be robust to noisy data, such as that which may be generated by Py-MS. 

Early pyrolysis-mass spectroscopy [14] and pyrolysis-gas chromatography [16] studies compared the breakdown of PET, PTT and PBT and, while providing no clear-cut reaction pathways, showed that all three polyesters appeared to thermally degrade via the same mechanism. 

R.A. Hwelwitskii, EM. Lubashenko, E.S. Brodskii in Pyrolysis Mass Spectroscopy of Macromolecules, Khimja, Moscow, Russia, 1980. 

Loss of two molecules of CO leads to arynes upon photolysis or severe thermolysis of benzocyclobutenedione (78) and plasmolysis or pyrolysis-mass spectroscopy of acenaphthenequinone (79). With both precursors the process appears to be stepwise as shown except, once again, under pyrolysis-mass spectroscopy conditions, which is consistent with a concerted loss of CO. ... 

Scherson DA, Tani a AA, Gupta GP, Tryk DA, Fierro C, Holze R, Yeager EB, Lattimer RP (1986) Transition metal macrocycles supported on high area carbon pyrolysis-mass spectroscopy studies. Electrochim Acta 31 1247-1258... 

Ford T, Sacco E, Black J, KeUey T, Goodacre R, Berkley RCW, MitcheU R (1991) Characterization of exopolymers of aquatic bacteria by pyrolysis-mass spectroscopy. Appl Environ Microbiol 57 1595—1601 Ford T, MitcheU R (1992) Microbial transport of toxic metals. In Mitchell R (ed) Environmental microbiology. WUey, New York, pp 83—101 Ford TE (1993) The microbial ecology of water distribution and outfaU systems. In Ford TE (ed) Aquatic microbiology an ecological approach. BlackweU Scientific, Boston, pp 455-482... 

Many analytical techniques have been utilized to analyze the SAN microstructure including LALLS [38], CNMR [19,31,39-44], infrared spectroscopy [45-49], ultraviolet spectroscopy [50-52], pyrolysis GC [8,27,53], pyrolysis mass spectroscopy [54,55], fluorescence [20,56], GPC-IR [57,58], and GPC-UV [52]. Since the terminal model allows the calculation of sequence distribution, the calculated and measured sequence distributions can be compared. This comparison generally shows deviation of the measured sequence distribution vs that predicted using the terminal model. Ham [59] was the first to notice the deviation and explained the deviation based upon penultimate effects. Since that time several other researchers have also notic deviation of their data from the terminal model and have applied more elaborate copolymerization models (Scheme 4) to explain the mechanism of SAN copolymerization. The penultimate [60,61] and complex participation models [33,62,63] have both been evaluated and give a better fit to the SAN system than the terminal model. 

Ghassempour A, Najafi NM, Amiri AA (2003) Determination of citric acid in fermentation media by pyrolysis mass spectroscopy. J Anal Appl Pyrolylis 70 251-261... 

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