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NANOTECHNOLOGYBy
K. Satya Sushma N. SatyaDevi
I.TBapatla Engineering College
[email protected] [email protected]
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Introduction:
Imagine a technology so powerful that it will allow
such feats as desktop manufacturing, cellular repair,
artificial intelligence, inexpensive space travel,
clean and abundant energy and environmental
restoration; a technology so portable that every one
can reap its benefits; a technology so fundamental
that it will radically change the economic and
political systems; a technology so imminent thatmost of people will see its impact within the
lifetimes. Such is the promise of nanotechnology.
. Albert Einstein first proved that each
molecule measures about a nanometer (a billionth
of a meter) in diameter. In 1959, it was Richard P.
Feynman who predicted a technological world
composed of self-replicating molecules whose
purpose would be the production of nano-sized
objects. Almost a hundred years after Einsteins
insight and 40 years after Feynmans initial
proposition, the nanometer scale looms large on the
research agenda. The semiconductor industry is
edging closer to the world of nanotechnology where
components are miniatured to the point of
individual molecules and atoms. A push is well
underway to invent devices that will manufacture
anything at almost no cost, by treating atoms
discretely, like computers treat bits of information.
This would allow automatic construction of
consumer goods without traditional labour, like a
Xerox machine produces unlimited retyping the
original information. Electronics is fuelled by
miniaturization. Working smaller has led to the
tools capable of manipulating individual atoms, just
as the proteins in a potato manipulate the atoms of
soil, water and air to make copies of themselves.
The shotgun marriage of chemistry and
engineering called nanotechnology is ushering in
the era of self-replicating machinery and self-
assembling consumer goods made from cheap raw
atoms
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What is Nanotechnology?
Nanotechnology aims at the design and
creation of functional materials, structures,
devices and systems through direct controlof matter on the nanometer length scale and
exploitation of novel phenomena and properties on this length scale. The length
scale is usually defined as being smaller than
100 nm, depending on the physical and
chemical characteristics of the particularsystem that undergoes quantitative and
qualitative changes when the length scale
boundary is crossed.
Nanotechnology research and development
includes manipulation under control of thenanoscale structures and their integration
into larger material components, systems
and architectures. Within these larger scale
assemblies, the control and construction oftheir structures and components remains at
the nanometer scale. Essential in
nanotechnology is to have a direct control ofmatter either between two nano-objects, or
between a micro (or macro) object and a
nano-object.
The nanoscale is about a thousand timessmaller than micro that is, about 1/80,000
of the diameter of a human hair.
Approximately 3 to 6 atoms can fit insideof a nanometer, depending on the atom.
The prefix nano means ten to the minusninth power, or one billionth. Nanoscale
technologies are the development and use
of devices that have a size of only a fewnanometers. Nanotechnologists
manipulate single molecules and atoms
At nano-scale, different laws come into play.
Properties of traditional materials change and
the behavior of surfaces starts to dominate the
behavior of bulk materials, opening up new
realms. In the electronic domain, the benefit of
working on nano-scale is production of smaller
things. Using nanotubes or other molecular
configurations enables engineers to break
through this barrier in the semiconductor
industry, which is expected to provide even
smaller circuits and even Scale of comparison,
more powerful computers, by working below
the wavelength of light, X-ray; etc. The
ultimate result is circuit elements consisting of
single molecules.
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VARIOUS DEFINITIONS:
Merriam-Webster's (Collegiate Dictionary
definition :) nanotechnologyPronunciation:"na-nO-tek-'n-lo-jE: the art of manipulating materials on an atomic or
molecular scale especially to build microscopic
devices (as robots)
Webopedia's
Definition of nanotechnology a field of science
whose goal is to control\individual atoms and
molecules to create computer chips and other
devices that are thousands of times smaller
than current technologies permit. Current
manufacturing processes use lithography toimprint circuits on semiconductor materials.
While lithography has improved dramaticallyover the last two decades-to the point wheresome manufacturing plants can produce
circuits smaller than one micron (1,000
nanometers)-it still deals with aggregates of
millions of atoms. It is widely believed thatlithography is quickly approaching its physical
limits. To continue reducing the size of
semiconductors, new technologies that juggleindividual atoms will be necessary. This is the
realm nanotechnology. Although researching
this field dates back to Richard P. Feynman'sclassic talk in 1959, the term
Nanotechnology was first coined by K. Eric Drexler in 1986 in thebookEngines of
Creation
After all the simple and understandable
definition of nanotechnology is given as:
Nanotechnology broadly refers to the
manipulation of matter on the atomic and
molecular scales i.e. where the objects of
interests are 0.1-100nm in size.
APPROACHES OF
NANOTECHNOLOGY:
The two fundamentally different approaches to
nanotechnology are graphically termed top-
down and bottom-up. Top down refers to
making nanoscale structures by machining and
etching techniques, whereas bottom-up, or
molecular nanotechnology, applies to building
organic and inorganic structures atom-by-atom,
or molecule-by-molecule. Topbottom or
bottom-up is a measure of the level of
advancement of nanotechnology.
Nanotechnology, as applied today, is still
mainly at what may be considered the more
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primitive bottom-top stage, building upward in
the Molecular scale as shown in the below
figure.
CONCEPTS OF
NANOTECHNOLGY:
There are two concepts commonly associated
with nanotechnology:
Positional Assembly
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Self-Replication
Clearly, we would be happy with any method that
simultaneously achieved the following three
objectives. However, this seems difficult without
using some form of positional assembly (to get the
right molecular parts in the right places) and some
form of self-replication (to keep the costs down).
1. Get essentially every atom in the right place.
2. Make almost any structure consistent with the
laws of physics and chemistry that we can specify
in atomic detail.
3. Have manufacturing costs not greatly exceeding
the cost of the required raw materials and energy.
TOOLS OF
NANOTECHNOLOGY:
The icons of this revolution are scanning probe
microscopesthe scanning tunneling microscope
(STM) and the atomic force microscope (AFM).
Both these machines have the ability to interact with
materials at the molecular level, although this is
limited. They are capable of creating pictures of
individual atoms or moving them from place to
place.
Researches at Cornell University created the worlds smallest guitar carved out of crystalline silicon and worlds smallest car and Taurus of
10nm using an atomic force microscope (AFM).
Drexler has proposed the Assembler, a nanosize
mechanical machine, which could manipulate atoms
precisely. These machines could be told to build
anything. To control these miniature run-abouts,
Drexler has designed the nanocomputer. This is not
an electronic device but one that would work on
rod-logic; a system of criss-crossing
mechanically-operated rods interacting with each
other. These computers would be small, typically
fitting inside a 400-nanometer cube, which is
approximately 1000 times smaller in volume than
one human cell. However, these would be as
powerful as some of todays desktop computers
CARBON NANOTUBES (Key
role in Nano Technology):
In 1991, carbon nanotube was discovered from the
cathode product in carbon-arc discharge method
similar to that used for fullerenes preparation. This
discovery opened a new chapter both in
nanotechnology and in. carbon chemistry
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Based on their unique properties, carbon nanotubesare expected to have variety of applications. A lot of
research has been carried out on synthesis,
characterization,
property measurement and applications of carbonnanotubes and will be continued. The structure of
nano tubes can be seen as shown
.
Various shapes and types of nanotubes (courtesy
www.nanoindustries.com )
REAL-WORLD NANO
EXISTS:In Medicine: Monitoring body state:
Given Imaging, an Israel company, has developed a
pill-size video camera that can travel through the
digestive track and transmit pictures along the way,
providing a less invasive technique to examine the
small intestines. This video camera uses a miniature
CMOS video imaging chip and white LED as a
light source
From left A DNA molecule attached to two electrodes, DNA structure, Future nano robos in medicine, Swan nano
In recent years nano technology is being used in the
field of medicine to an extent, they play a major
role in curing diseases like Cancer, Brain damage,
Harmone deficiency, Infection, hesterostasis,
Telomere loss, Chemical accumulation, DNA
damage etc.
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In Machinery:
Nanotechnology develops minute technology; this
is a model of "nanogears", as small as only a few
atoms wide. As science becomes more sophisticated
it naturally enters the realm of what is arbitrarily
labeled nanotechnology. The essence of
nanotechnology is that as we scale things down they
start to take on extremely novel properties.
Nanoparticles (clusters at nanometer scale), for
example, have very interesting
properties and are proving extremely useful as
catalysts and in other uses. If we ever do make
nanobots, they will not be scaled down versions of
contemporary robots.
Shapes Of Nanogears, Comparison between nanogears and a bug. (Courtesy www.iop.org)
In Space Research:
The stringent fuel constraints for lifting payloads
into earth orbit and beyond and the desire to send
spacecraft away from the sun for extended missions
(where solar power would be greatly diminished)
compel continued reduction in size, weight, and
power consumption of payloads. Nanostructured
materials and devices promise solutions to these
challenges. Nanostructuring is also critical to the
design and manufacture of lightweight, high-
strength, thermally stable materials for aircraft,
rockets, space stations, and planetary/solar
exploratory platforms.
Nano satellite (courtesy www.zyvex.com)
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TRANSPORTATION:Nanomaterials and
nanoelectronics will yield lighter, faster, and
safer vehicles and more durable, reliable, and
cost-effective roads, bridges, runways,
pipelines, and rail systems. The replacement of
carbon black in tires by nanometer-scale
particles of inorganic clays and polymers is a
new technology that is leading to the
production of environmentally friendly, wear-
resistant tires
ENVISAGED SUICIDES
Any powerful
technology can be used to do great harm as
well as great good. And Nanotechnology is no
exception to it. The concerns include:
ENVIRONMENTAL
CONTAMINATION
Smart drugs and other nano-devices usedin medical applications could
contaminate the environment
after being expelled from the body.
MUTATION:Smart drugs or other nano-devices
capable of manipulating organic
molecules could interact with cellular
activity in unexpected ways.Titanium dioxide, for example, is
used in sunscreens for its ability toreflect the sun's light and harmful UV
rays. At its nanoscale, it stops
reflecting light and therefore becomes
transparent - and thus morecommercially useful - while
maintaining its ability to reflect
harmful UV rays. Unfortunately,transparency isn't the only change.
Scientists from Oxford have observedthat at nanoscale titanium dioxide canalso pass through the skin and
damage the DNA of cells.
RUNAWAY CONDITIONA smart drug or nano-device capable of
replicating itself could result in a
runaway condition.
WEAPONS
This technology has the potential to be used as
a weapon that would be difficult to control.
Atomic properties could be exploited for
causing destruction
RECOMMENDATIONS:Given the tremendous
potential benefits of nanotechnology, and
the concern that it be developed withsensitivity to potential negative
implications, some recommendations are
quoted below.
Make support for social andeconomic research studies on
nanotechnology a high priority. Build
openness, disclosure, and public participation into the process of
developing nanotechnology research
and development program direction.
Establish a mechanism to inform,
educate, and involve the public
regarding potential impacts ofnanotechnology. The mechanism
should receive feedback from the
nanotechnology community, social
scientists, the private sector, and the
public. Create the knowledge base and
institutional infrastructure to evaluatenanotechnology scientific,
technological, and societal impacts
and implications from short-term (3
to 5 year), medium-term (5 to 20year), and long-term (over 20year)
perspectives.
Educate and train a new generation of
scientists and workers skilled in
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nanoscience and nanotechnology at
all levels with regard to societal
implications.
---SUGGESTIONS FOR PRIVATE
SECTOR
Provide intellectual input and seedfunding of activities aimed atassessing the societal implications of
nanotechnology.
Develop partnerships with academic
institutions and other sectors.
Offer accessibility to social scienceresearchers and provide feedback on
societal implications studies.
---SUGGESTIONS FOR
GOVERNMENT R&DLABORATORIES
Establish interdisciplinary teams for
major grand challenges innanotechnology including socio-
economic perspectives, including
social scientists.
Develop databases for evaluation and
continuously update scenarios for the
future. Establish user facilitiesavailable to industry and academe
that enable integration of basic and
applied research.
---SUGGESTIONS FORGOVERNMENT FUNDING
AGENCIES
Support nanotechnology researchers
and social scientists to study the
societal implications of nanotechnology.
Communicate the resulting activitiesto the public. Provide coordinated
support for long-term basic research
and shorter-term technologicaldevelopments to create thetechnological base and prove the
potential of the new technology.
Provide suggestions for grand
challenges and suggest warning signsof potential risks.
To take full advantage of the
new technology, the entire scientific and
technology community must involve allparticipants, including the general public
creatively envision the future; set broad
goals; and work together to expeditesocietal benefits.
CONCLUSION:
The paper concludes that the
argument is not to relinquish the
technological developments but to keepan eye on the ethical implications so that
we can take the full advantage of it. Man
had already made mistakes over themisuse of nuclear energy, GM products
etc. No more suicidal attempts can be
entertained that can relinquish humansafety. We have experienced to realize
the technological destruction faced bymankind today. No one can be made
responsible for this and unless we findways to safeguard ourselves, we are in
great trouble.
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REFERENCE:
1. ARTICLE NANOTUBE PEAPODS SCIENCE/ TECHNOLOGY, THE HINDU
10 Jan 2002
2. ARTICLE NANOWIRES SCIENCE /TECHNOLOGY, THE HINDU 14 FEB
2002
3. ARTICLE How Nanotechnology Could Help (Miniaturized?) Human Beings
ELECTRONICS FOR YOU MAY 2002
4 J.BR.Interplanet,Nanotechnology: Evolution of the concept
5 The Future Impact of Nanotechnology on textile technology and on textile industry
6 IEEE Instrumentation & Measurement Magazin4. Internet Link -
7 http://www.wtec.org/loyola/nano/NSET.Societal.Implications
8 Internet Link - http://www.phy.mtu.edu/
9 Internet Link http://science.howstuffworks.com/
10 Internet Link http://www.nano.org.uk/
11 Internet Link http://www.spectrum.ieee.org/WEBONLY/resource/
12 Internet Link http://guardianunlimited.com
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