Shaolin Ge

Development of a rapid method for the quantification of cellulose in tobacco by (13)C CP/MAS NMR.

A method was developed for rapid quantitative determination of cellulose in tobacco by utilizing (13)C cross polarization magic angle spinning NMR spectroscopy ((13)C CP/MAS NMR). Sample powder was loaded into NMR rotor, which was customized rotor containing a matched silicon tube as an intensity reference. (13)C CP/MAS NMR spectra of tobacco samples were processed with spectral deconvolution to obtain the area of the C-1 resonance at 105.5ppm and the internal standard at 0ppm. The ratio between the area of 105.5ppm and 0ppm of a set of standard cellulose samples was used to construct a calibration curve. The cellulose content of a tobacco sample was determined by comparison of the ratio between the area of 105.5ppm and 0ppm to the calibration curve. Results of this developed method showed good agreement with those obtained from chemical analysis. The proposed method has such advantages of accuracy, quickness and efficiency, and could be an alternative to chemical analyses of cellulose.

Influence of Ammonium Polyphosphate on Thermal Decomposition of Reconstituted Tobacco and CO Evolution

The thermal behaviors and burning characteristics of reconstituted tobacco (RT) are strongly related with evolved gaseous products. The effect of ammonium polyphosphate (APP) as an additive of RT on the pyrolysis behavior and CO evolution was studied, emphasizing the role of heating velocity in reducing CO delivery of the mainstream smoke by APP. Thermogravimetric analysis (TGA) was employed to investigate the influence of APP on RT thermal behavior. Slow and flash pyrolysis of RT were compared to discuss the role of heating rate in decreasing CO by APP. TGA results demonstrated that, in dependence on APP concentration, APP influenced exothermal amount and weight loss rate during RT thermal decomposition, promoted the formation of char and retarded the thermal decomposition of RT. In addition, APP had a considerable influence on the evolution of gaseous products during thermal decomposition of RT. Both CO delivery per cigarette and that per puff in the smoking process were significantly reduced in depende...