Nano
assembly , or 'bottom-up'
approach, similar to molecular
engineering,
the synthesis
of a nanostructured material by assembly of its
previously prepared nano-building-blocks
(nanoscopic particles, or even atoms
and molecules).
There are number of nano-assembly
techniques currently investigated. For example, nanoscopic particles can be
created in gas phase
(by evaporation of a material and clustering of atoms
and molecules
in the gas phase)
and then assembled together by a condensation/nucleation process, using possibly another
material (surfactant)
to prevent merging (agglomeration, coalescence)
of clusters.
Careful monitoring of thermodynamical parameters during this process can
result in nanostructured materials with varying
properties. Some futurists (Drexler) propose nanoscopic 'assemblers' (nanobots) which would compose a
nanoscopic particle or another nanobot on a molecule-by-molecule basis. This is, of course, only
speculative fiction concerning the present state
of science
and technology.
It is also questionable whether the science
we know about allows for such nanomachines
(Maxwell demons). Nevertheless, the operation of atomic force microscope in
assembling artificial structures such as corals can be considered as a rather
primitive example of this fiction.
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