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Nanotechnology
is the science
and technology
of precisely
structuring and
controlling
matter on the
nanometer scale.
Advancements in
nanotechnology
can be
classified in
three
categories:
• Information
Technology or
Molecular
Electronics
• Life/Health
Sciences or
Nanobiotechnology
• Material
Science-Nanotechnology
Nanomaterials
are materials
possessing grain
sizes on the
order of a
billionth of a
meter. They
manifest
extremely
fascinating and
useful
properties,
which can be
exploited for a
variety of
structural and
non-structural
applications.
Nano particles
are generally
described as
minute particles
of a few
nanometers in
size (one
nanometer is
one-billionth of
a meter). They
can be
recognized when
gathered into
clusters and
observed with
the aid of an
electron
microscope.
All materials
are composed of
grains, which in
turn comprise
many atoms.
These grains are
usually
invisible to the
naked eye,
depending upon
their size.
Conventional
materials have
grains varying
in size anywhere
from 100's of
microns (um) to
millimeters
(mm). A micron
is a micrometer
or a millionth
(10-6 ) of a
meter. An
average human
hair is about 30
um in diameter.
A nanometer (nm)
is one thousand
times smaller a
dimension than
um, and is a
billionth (10-9
) of a meter. A nanomaterial has
the grains on
the order of
1-100 nm. The
average size of
an atom is on
the order of 1-2
angstroms (Å) in
radius. One
nanometer
comprises 10 Å,
and hence in one
nm, there may be
3-5 atoms,
depending on the
atomic radii.
Nano materials
are
exceptionally
strong, hard and
ductile at high
temperatures,
wear resistant,
erosion-resistant
and
corrosion-resistant.
The size of a
nanometer is
equal to:
• 10- 9 meter =
one ten thousand
(1-10,000) the
diameter of a
human hair.
• 10 Angstroms =
Proportion of a
meter that a
golf ball is
compared to the
earth.
Nanometer sized
grains contain
thousands of
tens-of-thousands
of atoms as
compared to
billions or
trillions of
atoms in the
grains of
conventional
materials.
nanomaterials,
are also much
more formable
than their
conventional,
commercially
available
counter parts.
The products in
ultra fine
particles
present high
surface
activity, good
dispersibility
as well as
safety and
endurance to
heat.
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