Nano Nano!
From Wikipedia, the free
encyclopedia
Nanotechnology is a field of applied science and technology covering a
broad range of topics. The main unifying theme is the control of matter
on a scale smaller than 1 micrometre, normally approximately 1 to 100
nanometers, as well as the fabrication of devices of this size. It is a
highly multidisciplinary field, drawing from fields such as applied
physics, materials science, colloidal science, device physics,
supramolecular chemistry, and even mechanical and electrical
engineering. Much speculation exists as to what new science and
technology may result from these lines of research. Nanotechnology can
be seen as an extension of existing sciences into the nanoscale, or as a
recasting of existing sciences using a newer, more modern term.
Buckminsterfullerene C60, also known as the buckyball, is the
simplest of the carbon structures known as fullerenes. Members of
the fullerene family are a major subject of research falling under
the nanotechnology umbrella.
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Two main approaches are used in
nanotechnology. In the "bottom-up" approach, materials and devices are
built from molecular components which assemble themselves chemically by
principles of molecular recognition. In the "top-down" approach, nano-objects
are constructed from larger entities without atomic-level control. The
impetus for nanotechnology comes from a renewed interest in colloidal
science, coupled with a new generation of analytical tools such as the
atomic force microscope (AFM), and the scanning tunneling microscope (STM).
Combined with refined processes such as electron beam lithography and
molecular beam epitaxy, these instruments allow the deliberate
manipulation of nanostructures, and led to the observation of novel
phenomena.
Examples of nanotechnology in modern use are the manufacture of polymers
based on molecular structure, and the design of computer chip layouts
based on surface science. Despite the great promise of numerous
nanotechnologies such as quantum dots and nanotubes, real commercial
applications have mainly used the advantages of colloidal nanoparticles
in bulk form, such as suntan lotion, cosmetics, protective coatings, and
stain resistant clothing. |
