Abstract: Raincloud formation depends on the creation of Cloud Condensation Nuclei (CCN) around which water molecules cluster, generating a nano-particles (nano-cluster), then a micro-cluster and finally a water droplet. A collection of such water droplets constitutes a cloud which may spontaneously produce precipitation (in the form of rain, hail or snow) or precipitation induced by cloud seeding. The CCN is the result of nucleation processes. In this patent application, a process is described wherein said nucleation is catalyzed by the injection of a chemical substance, dimethylamine, into the upper atmosphere, preferably through injection of said substance into an electron rich aircraft engine exhaust. The subsequent formation of negatively charged ions has a catalytic effect on the generation of said CCNs.

Abstract: The invention relates to a material consisting of a preparation made from a mixture of ferrocene and an inert flameproof material such as plaster, the material being presented in the form of granules and being suitable for spreading over a hydrocarbon fire in a simple and rapid manner such that, under the effect of the heat from the fire, the ferrocene contained in the granulated material is diffused progressively and homogeneously in a vapor phase over the base of the flames, so as to optimize the combustion of the hydrocarbon and to reduce the emission of smoke and unwanted particles.

Abstract: The invention relates to a material consisting of a preparation made from a mixture of ferrocene and an inert flameproof material such as plaster, the material being presented in the form of granules and being suitable for spreading over a hydrocarbon fire in a simple and rapid manner such that, under the effect of the heat from the fire, the ferrocene contained in the granulated material is diffused progressively and homogeneously in a vapour phase over the base of the flames, so as to optimise the combustion of the hydrocarbon and to reduce the emission of smoke and unwanted particles.

Abstract: A low smoke firefighter training hydrocarbon composition and process. The compositions preferably contain alkanes and avoid aromatics. Ferrocene or certain other volatile iron compounds are incorporated in the compositions which am readily ignitable but not dangerously so. The process enhances the firefighter training while reducing smoke and soot to the surrounding environment.