Pyrolysis program structure

The pyrolysis high resolution mass spectrometry (PyHRMS) technique has been described in detail previously (20). Briefly, the coal sample was placed on a platinum rhodium mesh on the end of a probe as a slurry. After the solvent had evaporated, the probe was inserted into the mass spectrometer and positioned within 5 mm of the source. The probe, which had been previously calibrated with an infra-red thermometer, was computer-controlled to give a temperature profile beginning at 100°C and increasing at 50°C/min to 800 C. The precise masses were matched to their corresponding chemical structures by computer programs developed in-house. This technique results in the relatively slow vacuum pyrolysis of the coal sample. 

Titania-supported vanadia catalysts have been widely used in the selective catalytic reduction (SCR) of nitric oxide by ammonia (1, 2). In an attempt to improve the catalytic performance, many researchers in recent years have used different preparation methods to examine the structure-activity relationship in this system. For example, Ozkan et al (3) used different temperature-programmed methods to obtain vanadia particles exposing different crystal planes to study the effect of crystal morphology. Nickl et al (4) deposited vanadia on titania by the vapor deposition of vanadyl alkoxide instead of the conventional impregnation technique. Other workers have focused on the synthesis of titania by alternative methods in attempts to increase the surface area or improve its porosity. Ciambelli et al (5) used laser-activated pyrolysis to produce non-porous titania powders in the anatase phase with high specific surface area and uniform particle size. Solar et al have stabilized titania by depositing it onto silica (6). In fact, the new SCR catalyst developed by W. R. Grace Co.-Conn., SYNOX , is based on a titania/silica support (7). 

Adkins et al. also produced temperature-resolved pyrolysis results for ceU envelope fractions and whole cells of Salmonella typhimurium and for several Salmonella LPS samples. Model compounds (fatty acids, phospholipids, cholines, etc.) for LPS structures were also pyrolyzed using linear-programmed thermal degradation strategies. Common ions were found in the Py-MS fingerprints of cell wall components and the model compounds. Boon et al. °° applied Py-MS to the analysis... 

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