Critical temperature for the spontaneous ignition

The procedure to calculate the critical temperature for the spontaneous ignition or Tc for a gas-permeable oxidatively-heating substance, having some one of the several specific shapes above referred to as well as an arbitrary size, placed in the atmosphere under isothermal conditions, by applying the reduced form of the F-K equation, in the same manner as performed for a powdery chemical of the TD type, is introduced in Chapters 7 and 8. Principles and experimental procedures which are common to both powdery chemicals of the TD type and gas-permeable oxidatively-heating substances are, however, explained in the present chapter. 

Many research reports have appeared hitherto regarding various aspects of the thermal decomposition reaction or the combustion of woods or woody materials. However, instances in each of which the value of the critical temperature for the spontaneous ignition or for a bulky sawdust heap was actually measured have been only a few so far. In this regard, the works performed by Gross et al. [66], Akita [67], Anthony et al. [68], John [69] and Schliemann [70] are thought to be quite precious. 

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