The route by which gas-phase molecules in hydrocarbon flames form condensed-phase carbonaceous nanoparticles (incipient soot) is reviewed. These products of incomplete combustion are introduced as particulates and materials revealing both their useful applications and unwanted impacts as pollutants. Significant advances in experimental techniques in the last decade have allowed the gas phase precursors and the transformation from molecules to nanoparticles to be directly observed. These measurements combined with computational techniques allow for various mechanisms known to date to be compared and explored. Questions remain surrounding the various mechanisms that lead to nanoparticle formation. Mechanisms combining physical and chemical routes, so-called physically stabilised soot inception, are highlighted as a possible “middle way”.

综述了碳氢化合物火焰中气相分子形成凝聚相碳质纳米粒子（初始烟尘）的途径。这些不完全燃烧的产物作为微粒和材料被引入，揭示了它们作为污染物的有用应用和有害影响。过去十年中实验技术的重大进步使得可以直接观察气相前体和从分子到纳米颗粒的转变。这些测量与计算技术相结合，允许对迄今为止已知的各种机制进行比较和探索。关于导致纳米颗粒形成的各种机制的问题仍然存在。结合物理和化学途径的机制，即所谓的物理稳定烟尘开始，被强调为可能的“中间方式”。