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Diffusion Reaction Interaction for a Pair of Spheres - ETD ...

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probability P (2.55), and the concentration u pr<strong>of</strong>ile (2.68) in the neighborhood <strong>of</strong><br />

sphere 1 is completely specified. Both <strong>of</strong> the equations include a single infinite<br />

sum, which converges <strong>for</strong> all values <strong>of</strong> the dimensionless parameters γ, λ1 and d1.<br />

The infinite sum is calculated as a set <strong>of</strong> nested continued fractions, equations<br />

(2.40) – (2.43), generated from a system <strong>of</strong> linear equations. Then these types <strong>of</strong><br />

equations are easily solved as nested loop algorithm on a desktop computer.<br />

The reaction probability P, equation (2.55) contains a source term, sink<br />

term and a source-sink interaction series. The first factor comes from the<br />

monopole reactant concentration arising from the zeroth order reactant generation<br />

at the surface <strong>of</strong> the source. The monopole source concentration at any point<br />

from the center <strong>of</strong> the source is expressed as<br />

c m<br />

2<br />

σ 2a<br />

2<br />

= . (2.70)<br />

dD<br />

If the sink is immersed in the same medium with the uni<strong>for</strong>m concentration c at<br />

a center to center distance d from the source then the single sphere solution <strong>for</strong> a<br />

finite surface reaction rate is the well-known Smoluchowski diffusion-controlled<br />

reaction rate ( 4π Dc ) (Cukier, 1986 and Weiss, 1986) divided by the correction<br />

factor ( 1<br />

a 1<br />

m<br />

1 + λ ) <strong>for</strong> the finite surface reaction rate (Reid, 1952). Then <strong>for</strong> larger<br />

sink-source separation distances i.e., the monopole sink reaction rate is<br />

37<br />

m<br />

d

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