Improved reaction chamber designs are described that provide for improved
control over the flow within the reaction chamber. The reaction chambers contain
reactions for particle production from a flowing reactant stream. Improved reactant
delivery nozzles are described that are useful for the delivery of gas/vapor reactants
and/or aerosol reactants. Improved nozzle designs can result in more uniform reactant
flow. Suitable reactors can comprise an electromagnetic radiation source that projects
through the reactor to drive the reaction at an electromagnetic radiation reaction
zone. The improved nozzle features are suitable for reactors for particle collection
and/or for coating of substrates within the reaction chamber.
