phase consists of those elements in the gas phase when the liquid
droplets solidify.
The refractory phase consists of those elements in
the liquid droplets when they solidify.
The volatile/refractory ratio
is the ratio of the amounts of volatile phase to refractory phase,
denoted by r(A) for mass chain A.
Consider for the moment only the material vaporized by the
detonation.
The condensate is in the form of small spheroids and the
refractory nuclides are assumed to be distributed uniformly throughout
the volume of the droplet (amount varies as r°).
The volatile
nuclides are assumed to be distributed uniformly over the surface
(amount varies as r’).
The volatile/refractory ratio associated with
a given particle will vary as rl:
the smaller the particle, the
larger the proportion of volatile phase.
This ideal picture becomes complicated because spheres of debris
can attach to each other or to unmelted dust particles which have been
entrained by the cloud.
irregular particles.
The result is a mixing of spherical and
This mixing should tend to reduce the strong
dependence of the volatile/refractory ratio on the size of -particles
collected in the field.
The solid particles in the cloud of nuclear debris fall to earth
at different velocities and from different altitudes.
This process has
the effect of separating the debris by particle size along the path of
the cloud.
Thus, the refractory phase and the volatile phase are