Pyrolysis of sample

Experimental conditions are listed in Table 2. After pyrolysis of samples at 1073K, the product char was washed with pure water and chlorine of the leachates was analyzed by ion chromatography. Refer to the reference [3] for a detailed experimental procedure. 

For these reasons, when the pyrolysis of samples from works of art is undertaken for the first time, as well as when a new device or a new instrumental set-up is introduced in a laboratory, it is very important to build one s own libraries of chromatographic profiles, based on the analysis of reference materials. 

INAN, S., Yalcin, M. N. Mann, U. 1998. Expulsion of oil from petroleum source rocks, inferences from pyrolysis of samples of unconventional grain size. In Horsfield, B., Radke, M., Schaefer, R. G. Wilkes, H. (eds) Advances in Organic Geochemistry 1997. Organic Geochemistry, 29,45-61. 

Py-GC, in its early stage, however, had some serious limitations such as difficulty in attaining specific pyrolysis of samples, insufficient chromatographic... 

The third way to introduce the dopant element consists in the pyrolysis of samples with precursors containing carbon and the dopant element [16-17] (Scheme 3.7). In this case it is important to control the pyrolysis conditions, particularly the temperature, since, as a general trend, an increase in the pyrolysis temperature decreases the percentage of the dopant element by producing Gs with higher quality and lower density of defects. 

H. Anderson [11] used differential thermal and thermogravimetric analyses to confirm the free radical mechanism of the thermal decomposition of epoxide resins, proposed by M. B. Neiman and associates. It was shown in this work that an important stj e in the pyrolysis of an epoxide resin is isomerization of the epoxide group to a carbonyl, which is accompanied by an exothermic effect and is observed in the temperature interval 350-400°C. The thermogravimetric curves confirmed that the rate of pyrolysis of samples of epoxide resins hardened with maleic anhydride is less than that of samples hardened with amines (metaphenylenediamine). 

Pyrolysis of sample followed by gas-liquid chromatography (GLC) of pyrolysis products. 

Continual use of decabromidiphenyl oxide has been placed ia question based on the discovery that under certain laboratory conditions brominated dibenzo- -dioxias are generated (63). The condition most often employed ia such studies is pyrolysis of milligram-scale samples at 600°C. This temperature is higher than polymer processiag conditions and lower than fire temperatures, ie, the conditions are not representative of actual conditions to which flame-retardant polymers are exposed. 

Sample preparation for the modified Fischer assay technique, a standard method to determine the Hquid yields from pyrolysis of oil shale, is necessary to achieve reproducible results. A 100-g sample of >230 fim (65 mesh) of oil shale is heated in a Fischer assay retort through a prescribed temperature range, eg, ca 25.5—500°C, for 50 min and then soaked for 20 min. The organic Hquid which is collected is the Fischer assay yield (7). The Fischer assay is not an absolute method, but a quaHtative assessment of the oil that may be produced from a given sample of oil shale (8). Retorting yields of greater than 100% of Fischer assay are possible. 

The analysis of industrial samples such as the pyrolysis products of Turkish lignites has been carried out by using GC, SEC and coupled HPLC/GC (16). The combustion products of lignites result in atmospheric pollution. The pyrolysis of... 

Pyrolysis gas chromatography is an indirect method of analysis in which heat is used to transform a sample into a series of volatile products characteristic of sample and the... 

Liquid (solvent) extraction is not the only way of sample preparation, but stands along with various forms of heat extraction (headspace, thermal desorption, pyrolysis, etc.) and with laser desorption techniques. 

To use the DCI probe, 1-2 xL of the sample (in solution) are applied to the probe tip, composed of a small platinum coil, and after the solvent has been allowed to evaporate at room temperature, the probe is inserted into the source. DCI probes have the capability of very fast temperature ramping from 20 to 700 °C over several seconds, in order to volatilise the sample before it thermally decomposes. With slower temperature gradients, samples containing a mixture of components can be fractionally desorbed. The temperature ramp can be reproduced accurately. It is important to use as volatile a solvent as possible, so as to minimise the time required to wait for solvent evaporation, which leaves a thin layer of sample covering the coil. The observed spectrum is likely to be the superposition of various phenomena evaporation of the sample with rapid ionisation direct ionisation on the filament surface direct desorption of ions and, at higher temperature, pyrolysis followed by ionisation. 

Intact bacteria were first introduced into a mass spectrometer for analysis of molecular biomarkers without processing and fractionation around 1975.6 The ionization techniques available at the time limited analysis to secondary metabolites that could be volatilized, such as quinines and diglycerides, and vigorous pyrolysis of bacteria was explored as an alternative.7 Although biomarkers were destroyed in pyrolysis strategies, computer-supported cluster analysis was developed to characterize pure samples. 

Windig, W. Kistemaker, P. G. Haverkamp, J. Meuzelaar, H. L. C. The effects of sample preparation, pyrolysis and pyrolysate transfer conditions on pyrolysis mass spectra. J. Anal. Appl. Pyrolysis 1979,1, 39-52. 

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