Uploaded by ICAY

Sts Nanotech

advertisement
Senajon, Angelica Faye N.
BSMLS 1-G STS – Homework
April 24, 2019
A Look Into Nanotechnology
Nanotechnology refers broadly
to a field of applied science and
technology whose unifying theme is
the control of matter on the molecular
level
in
scales
micrometre,
smaller
normally
1
than
to
1
100
nanometers, and the fabrication of
devices within that size range. 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.
Two main approaches are used in nanotechnology. First is the "bottom-up"
approach, materials and devices are built from molecular components which assemble
themselves chemically by principles of molecular recognition. Second is 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. Modern synthetic chemistry has reached the point where it is possible
to prepare small molecules to almost any structure.
These methods are used today to produce a wide variety of useful chemicals such
as pharmaceuticals or commercial
polymers. This ability raises the
question of extending this kind of
control to the next-larger level,
seeking methods to assemble
these
single
supramolecular
molecules
into
assemblies
consisting of many molecules
arranged in a well-defined manner.
These approaches utilize the concepts of molecular self-assembly and/or
supramolecular chemistry to automatically arrange themselves into some useful
conformation through a bottom-up approach. The concept of molecular recognition is
especially important: molecules can be designed so that a specific conformation or
arrangement is favored due to non-covalent intermolecular forces.
The Watson-Crick base-pairing rules are a direct result of this, as is the specificity
of an enzyme being targeted to a single substrate, or the specific folding of the protein
itself. Thus, two or more components can be designed to be complementary and mutually
attractive so that they make a more complex and useful whole.
There's an unprecedented multidisciplinary convergence of scientists dedicated to
the study of a world so small, we can't see it -- even with a light microscope. That world
is the field of nanotechnology, the realm of atoms and nanostructures.
Nanotechnology is so new, no one is really sure what will come of it. Even so,
predictions range from the ability to reproduce things like diamonds and food to the
world being devoured by self-replicating nanorobots.
In a lecture called "Small Wonders:The World of Nanoscience," Nobel Prize winner
Dr. Horst Störmer said that the nanoscale is more interesting than the atomic scale
because the nanoscale is the first point where we can assemble something -- it's not until
we start putting atoms together that we can make anything useful.
One of the exciting and challenging aspects of the nanoscale is the role that
quantum mechanics plays in it.
The rules of quantum mechanics
are very different from classical
physics, -which means that the
behavior of substances at the
nanoscale
can
sometimes
contradict common sense by
behaving erratically. You can't
walk up to a wall and immediately
teleport to the other side of it, but
at the nanoscale an electron can - it's called electron tunneling.
Substances
that
are
insulators, meaning they can't
carry an electric charge, in bulk
form
might
become
semiconductors when reduced to the nanoscale. Melting points can change due to an
increase in surface area. Much of nanoscience requires that you forget what you know
and start learning all over again.
So, what does this all mean? Right now, it means that scientists are experimenting
with substances at the nanoscale to learn about their properties and how we might be
able to take advantage of them in various applications. Engineers are trying to use nanosize wires to create smaller, more powerful microprocessors. Doctors are searching for
ways to use nanoparticles in medical applications. Still, we've got a long way to go before
nanotechnology dominates the technology and medical markets.
Nanotechnology can almost be applied in our everyday lives. One application of
nanotechnology in medicine currently being developed involves employing nanoparticles
to deliver drugs, heat, light or
other
substances to
specific
types of cells, such as cancer
cells. Particles are engineered so
that
they
are
attracted
to
diseased cells, which allow direct
treatment of those cells. This
technique reduces damage to
healthy cells in the body and
allows for earlier detection of
disease.
For
example,
nanoparticles that deliver chemotherapy drugs directly to cancer cells are under
development.
Nanoelectronics holds some answers on expanding the capabilities of electronics
devices can be expanded while reducing their weight and power consumption. These
include improving display screens on electronics devices and increasing the density of
memory chips. Nanotechnology can also reduce the size of transistors used in integrated
circuits. One researcher believes it may
be possible to put the power of all of
today’s present computers in the palm
of your hand.
References:
Bradley, P. (2013). Everyday applications of nanotechnology. Community College Week.
Retrieved
from
http://ccweek.com/article-2630-everyday-applications-of-
nanotechnology.html on April 23, 2019
Bonsor, K. & Strickland, J. (n.d.). How nanotechnology works. How Stuff Works. Retrieved
from https://science.howstuffworks.com/nanotechnology4.htm on April 23, 2019
Physics Org. (n.d.). Nanotechnology news. Retrieved from https://phys.org/nanotechnews/ on April 23, 2019
Science
Daily,
(n.d.).
Nanotechnology.
Retrieved
https://www.sciencedaily.com/terms/nanotechnology.htm on April 23, 2019
from
Download
Random flashcards
Radiobiology

39 Cards

Radioactivity

30 Cards

Nomads

17 Cards

History of Europe

27 Cards

Create flashcards