NanoTechnology

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NanoTechnology
heres what it means

• Nano one billionth. Something divided into a
  million bits then each bit divided into a
  thousand smaller bits.
• Technology building things.
• Nanotechnology building things from very tiny
  parts.

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• Nanotechnology is a buzz word.
• There is lots of hype about it.
• But .There is nothing fundamentally new about
  making things from tiny parts.
• It has been happening in nature ever since the
  universe began

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living things are made from cells.
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and all substances are made from atoms.
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• Whats new is the technology part.
• Through science we understand much about how tiny
  objects workabout atoms molecules and
  cells.
• Now we can start to copy what happens in nature
  and to make new things using these methods.

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In nature objects of tiny size are formed all the
time. Tiny objects, atoms, molecules, cells,
join together to make larger and more complex
things. The natural world around us is made of a
vast number of interacting parts, building up in
size from very tiny to very large.
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Until recently our crafts and technologies have
been able to work only with objects that have
sizes on the human scale from hundreds of
metres to a fraction of a millimetre. Though
science technology humans now have the ability
to manipulate tiny sized objects smaller than
the parts in a living cell. Even as small as
individual atoms.
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Picture source cnx.org/content/m14353/latest/
Individual atoms placed with Scanning Tunnelling
Microscope (STM)
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Iron atoms on copper formed with Scanning
Tunnelling Microscope (STM) Image source
http//www.cite-sciences.fr/english/ala_cite/exhib
itions/nanotechnologies/images/diapo01/04-stm11.jp
g
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Nanotechnology is the ability to work with
objects on the nanoscale. We can work with these
tiny objects in many different ways.
Before looking at these in more detail we will
try to get an idea of the size of the objects
which exist in the nano-world.
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A journey from the everyday world to the
nano-world.
100 m 10-1 m 10-2
m 10-3 m 10-4 m 1
metre 1 centimetre 1 millimetre
10-5 m 10-6 m 10-7 m
10-8 m 10-9 m 10-10 m 1
micrometre
1 nanometre
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A photograph about 1 metre across 100 metre
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A photograph about 10 cm across 10-1 metre
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A photograph about 1 cm across 10-2 metre
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A photograph through light microscope about 1 mm
across 10-3 metre
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A photograph through light microscope about 0.1
mm across 10-4 metre
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A photograph through light microscope about 0.01
mm across 10-5 metre
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Electron microscope image about 0.001 mm across
10-6 metre
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Electron microscope image about 0.0001 mm across
10-7 metre
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Computer generated image about 0.00001 mm across
10-9 metre
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Computer generated image about 0.000001 mm across
10-9 metre
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Computer generated diagram about 0.0000001 mm
across 10-10 metre
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In our everyday technologies we have different
approaches to making things.
Here are two examples from the (ancient) building
industry.
We can start with large objects and work down, by
removing material, until we get the shape we want.
We can start with small objects and work up, by
adding material, until we get the shape we want.
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We sometimes reshape material like a potter.
We sometimes work away a material like a
sculptor.
We sometimes combine materials like house
builder.
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Temple hewn from solid rock. Ellora caves,
central India
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Pyramid built from individual blocks of
stone. Egypt
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• Nanotechnology also means working in many ways
• reshaping materials
• carving smaller parts from larger ones
• combining different materials
• building large objects from smaller units
• All at the nano scale with things about a
  thousand millionth of a metre in size.

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Some simple existing applications of
nanotechnology Sunscreenhttp//www.oxonica.com/o
ptisol.htm Self cleaning windowshttp//www.chippi
ngsodburyglass.co.uk/selfclean.htm Catalyst for
diesel engines http//www.cerulean-international.
com/products.htm Nanodiamondshttp//www.plasmache
m.com All these are based just on the small
size of the particles.
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Nano crystals of titanium dioxide absorb ultra
violet radiation but dont affect visible
light. Larger particles in ordinary sunscreen
reflect visible light and so appear white. As
the nano crystals are much smaller than the
wavelength of visible light that light passes
through the nano layer it is transparent. So
we have sunscreen which is invisible but it more
effective at blocking uv than regular sunscreen.
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Self cleaning glass has a nanolayer of titanium
dioxide coating on the surface. This acts in two
ways First, it is photocatalytic UV rays,
abundant on even the cloudiest of days, cause the
glass to react chemically with dirt and organic
deposits, breaking them down and loosening them
from the surface of the glass.
Secondly, it is hydrophilic it attracts water,
which slides down and off the surface of the
glass without forming into separate droplets.
This ensures that loose particles of dust and
dirt are easily washed off during normal rainy
weather.
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Envirox fuel additive is a scientifically and
commercially proven diesel fuel combustion
improver which reduces fuel consumption and also
reduces harmful exhaust emissions. It is based
on the use of cerium oxide nanoparticles which
are a catalyst for the burning of carbon . Any
carbon particles left from the diesel fuel burn
up at lower temperature. The exhaust is cleaner
and more energy is obtained which lowers fuel
consumption
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• Nano sized diamonds with an average diameter of
  4 nano-metre, have many uses including polishing
  of
• Lapping and polishing applications
• Nickel Plated Rigid Memory Disk
• Al-Rigid Memory Disk Substrate
• Polycarbonate and CR-39 Eyeglass Lenses
• Miniature and Precision Ball Bearings
• Optical and Laser Optical Components
• Orthopedic Prostheses
• Precious Stones
• Honing Microtome Knives
• Stainless Steel Sheet
• Metallic Mirrors and Precision Metal Polishing
• Acrylic Sheet, Aircraft Windows and Canopies
• Contact Lenses
• Superhard and Soft Nanoabrasives
• Polishing of PC Hard Disc

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More advanced nano devices in use or being
developed nanosensors for medical use DNA
Chiphttp//www.plasmachem.com Bio-assay via
Raman scatteringhttp//www.oxonica.com/biodiag2.
htm Fluorescent nanocrystals for medical
diagnosticshttp//www.oxonica.com/biodiag1.htm
Carbon nanotubes to monitor changes in
breathinghttp//www.nature.com/news/2004/041108//
full/041108-18.html
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Some other nanotechnology applications Lotus
leaf effect Gecko tape (van der Waals forces
controlled ! ) etc.
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Hydrophobic surfaces based on Lotus leaf
principle
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Some existing applications of lotus effect
surface treatment.
Stain resistant clothing from NanoTex fabrics
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Gecko Tape.
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Production of color by precise control of
nanoscale structure as in a butterfly wing.
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Quantum Dots - CdSe of precisely controlled
particle size. CdSe is a semiconductor and
restricting the size of the particles to nano
dimensions also confines the conduction band
electrons. The fluorescent wavelength can be
precisely controlled. This has gone from lab
discovery to commercial production in about a
decade.
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Another type of Nanotechnology modifying natural
nanoscale systems. Modifying DNA? Making
artificial genes? Creating new letters for
genetic alphabet (to add to natural CTGA) Making
a minimum living organismRemoving genes from
a cell, one by one, to find the smallest set of
genes with which the cell can still
live. Creating a living cell entirely from non
living starting materials
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More complex systems Nano-machines DNA
replication is a natural machine at the
nanoscale. The DNA double helix is unwound, then
the CTGA bases in each strand are paired with
their complements to form two new double helix
lengths of DNA each an exact copy of the
original. Movies of DNA replicationnatures
nanomachinery (Internet link required )
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Inorganic machines. Nanoscale machines can be
made that are not based on the chemicals in
living things. They might be copies of large
scale machines such as electric motors and
contain familiar parts such as roller bearings.
Nothing like this exists in nature. Materials
built from small units like this might be very
useful. Living cells in animals and plants have
parts that have evolved to extract energy (from
sunlight, from glucose etc) and essentially just
build new cells. Imagine copying the complexity
of organisms but replacing the living cells with
nano scale motors, gears etc and with energy
extracted from sunlight, or heat or a suitable
fuel, and designed to produce almost anything we
can imagine rather than just copies of
themselves. Building atom by atom opens enormous
possibilities.
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Many of these parts have been designed
Some have been produced
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This might seem very far fetched, but we know
that even just the arrangement of atoms has
dramatic effects. Carbon atoms arranged one way
form diamond
Arranged another way they form graphite
And in another arrangement they form charcoal
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If we use more than one type of atom the
possibilities are increased. We know that living
things are made up of many interacting tiny
parts, yet they are made of a limited range of
atoms, and have just a few basic ways of
obtaining energy. Its hard to even imagine what
might be made when we assemble things atom by
atom, without any of the limitations that we see
in living systems.
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Nanotechnology means any technology we devise
that manipulates things about a billionth of a
metre in size. There are lots of ways of doing
this. Some practical applications already exist,
but we are just at the beginning of the
nanotechnology age and we cant even imagine all
the possible ways nanotechnology will be used -
even in the near future.
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Animations of imagined nanotechnology factory
(broadband connection needed for movies, slide
sets over dial-up connections) Google Movie of
nanotechnology production