Chemi-ion precursors

Radical and Chemi-ion Precursors Electric Field Efiects in Soot Nucleation... 

Pyrolysis reactions are undoubtedly occurring after combustion, and chemi-ionization may be occurring in addition to charge exchange reactions between primary ions, such as CsHs, and light hydrocarbons. Hence, the chemi-ion profile would not decay necessarily as it does in leaner combustion, where recombination begins to dominate ion formation. Instead, a different sequence of chemi-ion reactions may become important, with the precursor being C2, rather than CH. 

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