Geoscience Reference
In-Depth Information
PARTICLE SIZE (in nm)
0
10
20
30
40
50
60
1.6
ε
=100
ε
=5
ε
=2
1.4
q=Q=1
1.2
1.0
0.8
0.6
0.4
0.2
0.0
0.2
0.4
0.6
0.8
1.0
PARTICLE SIZE (in units of l
c
)
Fig. 3.11
Suppression factor ".a/ as the function of particle size for double charging of similarly
charged particles.
Lower horizontal axis
shows particle size in units of the Coulomb length
l
c
D
ˇe
2
is found and then matched to that found in the diffusion limit. We introduce three
matching parameters: the ion flux, the matching distance, and the ion density at the
particle surface. Three conditions are formulated for fixing these parameters: (1) the
constancy of the total ion flux, (2) the continuity of the ion concentration profile, and
(3) the continuity of the derivative of the ion concentration profile. This approach is
applied for calculating the efficiencies of particle charging in the transition regime
(the particle size is comparable to the ion mean free path and the Coulomb distance
l
c
D
e
2
=kT).
3.6.1
Free Molecule Ion Distribution
Before constructing the general solution to the kinetic equation describing the
motion of ions in the free molecule regime, we find first the interval of angular
