Pyrolysis mass spectroscopy, chemical

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. 

Saiz-Jimenez, C. and de Leeuw, J. W., Chemical characterization of soil organic matter by analytical pyrolysis-gas chromatography-mass spectroscopy, J. Anal Appl Pyrolysis, 9, 99-119, 1986. 

Saiz-Jimenez, C. and de Leeuw, J. W., Chemical characterization of soil organic matter by analytical pyrolysis-gas chromatography-mass spectroscopy, J. Anal. Appl. Pyrolysis, 9, 99-119, 1986. Lehtonen, T., Peuravuori, J., and Pihlaja, K., Degradation of TMAH treated aquatic humic matter at different temperatures, i. Anal. Appl. Pyrolysis, 55, 151-160, 2000. 

Ballistreri and co-workers [59] examined the primary thermal decomposition mechanism of this polymer by Py-MS. Several MS techniques were used to identify compounds present in the pyrolysis mixture comparison of electron impact and chemical ionisation spectra, high resolution accurate mass measurements and tandem mass spectroscopy (daughter and parent ion spectra). The results obtained indicate that intramolecular exchange reactions predominate in the primary thermal fragmentation processes yielding cyclic oligomers up to tetramer. No other pyrolysis products were detectable. 

Dan and co-workers [8] studied the structures and thermal and thermo-oxidative stabilities of the gel and chlorinated natural rubber from latex. The polymers were analysed by chemical analysis, high-resolution pyrolysis-gas chromatography-mass spectroscopy (HR-Py-GC-MS) coupled with Fourier-transform infrared spectroscopy, and thermal analysis techniques [dynamic thermal analysis and thermogravimetric analysis (TGA)]. 

A novel, soluble trimetallic double alkoxide precursor to potassium aluminosilicate (KAlSi04) has been synthesized by a one pot procedure and its structure characterized. The process termed the oxide one pot synthesis (OOPS) process uses simple, inexpensive chemicals, silica and aluminum hydroxide, to form a processable precursor in one simple step. The precursor is relatively stable to moisture and can be handled in air for long periods of time with minimal hydrolysis. On pyrolysis in air, to 1100" C, it produces phase-pure KAlSi04. The proposed precursor was characterized using thermogravimetric analysis, multinuclearNMR, and mass spectroscopy. The results suggest the precursor disproportionates in solution. 

Chemical Analysis. The presence of siUcones in a sample can be ascertained quaUtatively by burning a small amount of the sample on the tip of a spatula. SiUcones bum with a characteristic sparkly flame and emit a white sooty smoke on combustion. A white ashen residue is often deposited as well. If this residue dissolves and becomes volatile when heated with hydrofluoric acid, it is most likely a siUceous residue (437). Quantitative measurement of total sihcon in a sample is often accompHshed indirectly, by converting the species to siUca or siUcate, followed by deterrnination of the heteropoly blue sihcomolybdate, which absorbs at 800 nm, using atomic spectroscopy or uv spectroscopy (438—443). Pyrolysis gc followed by mass spectroscopic detection of the pyrolysate is a particularly sensitive tool for identifying siUcones (442,443). This technique rehes on the pyrolytic conversion of siUcones to cycHcs, predominantly to [541-05-9] which is readily detected and quantified (eq. 37). 

Sulfenic acid (3) has been synthesized in the gas phase by low-pressure, high-temperature pyrolysis of di-t-butyl sulfoxide (4) and characterized by means of matrix isolation and gas-phase IR spectroscopy (Scheme 4).32 The mechanism of formation of (3) by flash pyrolysis of (4) has been studied by quantum chemical calculations, and different pyrolysis experiments monitored by mass spectrometry. In agreement... 

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