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-DHYANA BAXI(13BEE032
-NEHA SAXENA(13BEE061)
O
• Nanotechnology is the manipulation of
matter with at least one dimension sized from
1 to 100 nanometers.
• It has been discovered that as the size
decreases, the surface to volume ratio
increases drastically which changes the elastic,
mechanical, optical and thermal properties of
the matter.
• This has opened up new horizons in physics.
• Carbon nanotubes (CNTs) are allotropes of
carbons with a cylindrical nanostructure.
Nanotubes have been constructed with length-todiameter ratio of up to 132,000,000:1, significantly
larger than for any other material.
• These cylindrical carbon molecules have unusual
properties, which are valuable for
nanotechnology, electronics, optics and other
fields of materials science and technology. They are
used as additives to various structural materials.
For instance, nanotubes form a tiny portion of the
material(s) in some baseball bats, golf clubs, or car
parts or in reva.
• Nanotubes are members of the fullerene structural
family. Their name is derived from their long, hollow
structure with the walls formed by one-atom-thick
sheets of carbon, called graphene. These sheets are
rolled at specific and discrete ("chiral") angles, and the
combination of the rolling angle and radius decides the
nanotube properties; for example, whether the
individual nanotube shell is a metal or semiconductor.
Nanotubes are categorized as single-walled
nanotubes(SWNTs) and multi-walled
nanotubes(MWNTs). Individual nanotubes naturally
align themselves into "ropes" held together by van der
Waals forces, more specifically, pi-stacking.
The size of nanomaterials is similar to that of most biological
molecules and structures; therefore, nanomaterials can be
useful for both in vivo and in vitro biomedical research and
applications. Thus far, the integration of nanomaterials with
biology has led to the development of diagnostic devices,
contrast agents, analytical tools, physical therapy applications,
and drug delivery vehicles.
Nanomedicine seeks to deliver a valuable set of research tools
and clinically useful devices in the near future.
Nanotechnology has provided the possibility of delivering drugs to specific cells
using nanoparticles. The overall drug consumption and side-effects may be
lowered significantly by depositing the active agent in the morbid region only and
in no higher dose than needed. This highly selective approach would reduce costs
and human suffering. An example can be found in dendrimers and nanoporous
materials. Another example is to use block co-polymers, which form micelles for
drug encapsulation. They could hold small drug molecules transporting them to the
desired location. Another vision is based on small electromechanical
systems; nanoelectromechanical systems are being investigated for the active
release of drugs. Some potentially important applications include cancer treatment
with iron nanoparticles or gold shells. A targeted or personalized medicine is
intended to reduce the drug consumption and treatment expenses resulting in an
overall societal benefit by reducing the costs to the public health system.
The small size of nanoparticles endows them with properties that can
be very useful in oncology, particularly in imaging. Quantum dots
(nanoparticles with quantum confinement properties, such as sizetunable light emission), when used in conjunction with MRI (magnetic
resonance imaging), can produce exceptional images of tumor sites.
These nanoparticles are much brighter than organic dyes and only
need one light source for excitation. This means that the use of
fluorescent quantum dots could produce a higher contrast image and
at a lower cost than today's organic dyes used as contrast media. The
downside, however, is that quantum dots are usually made of quite
toxic elements.
American football is a collision sport. And one consequence of
repeated collisions between players is concussions. Science is
starting to draw a link between these so-called mild brain injuries
and the long-term effects they have on the players—namely the
onset of chronic traumatic encephalopathy (CTE), a degenerative
condition believed to be caused by head trauma and linked to
depression and dementia
The heart of the technology is smart foam enabled by
nanoparticles, The nano-enabled foam behaves as a piezoelectric in
which pressure on the material produces an electrical voltage. A
microcontroller sensor in the helmet reads the electrical voltage
produced by the foam, and sends a signal to a handheld tablet
equipped with a program that interprets it and delivers real-time
information on the seriousness of the hit sustained by the player.
In modern day tennis equipment, nanotech is widely used
to increase the durability, efficiency and safety factor of
the various equipments.
1) silicon dioxide particles are used in racquet heads to
make them faster and at times increase the spin factor of
the racquet.
2) nanoparticles are used to fill the minute spaces in the
balls and make them lighter and bouncier.
3) certain nanoparticles used as fillings decrease the risk of
abrasion to players while using the racquets
Several companies now offer a product they call Activ Glass, which
uses nanoparticles to make the glass photocatalytic and hydrophilic.
The photocatalytic effect means that when UV radiation from light
hits the glass, nanoparticles become energized and begin to break
down and loosen organic molecules on the glass (in other words,
dirt). Hydrophilic means that when water makes contact with the
glass, it spreads across the glass evenly, which helps wash the glass
clean.
This technology can be used to make glass articles like table tops,
mirrors, showpieces etc. It will help to save time, energy and money
required to clean the articles on a daily basis. Also it offers a more
efficient way to clean the articles.
Scientists are using nanoparticles to enhance clothing. By coating
fabrics with a thin layer of zinc oxide nanoparticles, manufacturers
can create clothes that give better protection from UV radiation.
Some clothes have nanoparticles in the form of little hairs or
whiskers that help repel water and other materials, making the
clothing stain-resistant.
Scratch-resistant coatings - Engineers discovered that adding
aluminum silicate nanoparticles to scratch-resistant polymer
coatings made the coatings more effective, increasing resistance to
chipping and scratching. Scratch-resistant coatings are common on
everything from cars to eyeglass lenses.
Over the past few decades, the fields of science and
engineering have been seeking to develop new and
improved types of energy technologies that have the
capability of improving life all over the world. In order
to make the next leap forward from the current
generation of technology, scientists and engineers
have been developing energy applications of
nanotechnology.
ConsERV, a product developed by the Dais Analytic
Corporation, uses nanoscale polymer membranes to
increase the efficiency of heating and cooling systems and
has already proven to be a lucrative design. The polymer
membrane was specifically configured for this application
by selectively engineering the size of the pores in the
membrane to prevent air from passing, while allowing
moisture to pass through the membrane. ConsERV's value
is demonstrated in the form of an energy recovery a device
which pretreats the incoming fresh air to a building using
the energy found in the exhaust air steam using no moving
parts to lower the energy and carbon footprint of existing
forms of heating and cooling equipment
Nanocap, a product by a US based company, uses
nanotechnology to create an energy storage mechanism
projected to have performance and cost advantages over
existing storage technologies. NanoCap is a form of ultracapacitor potentially useful to power a broad range of
applications including most forms of transportation, energy
storage (especially useful as a storage media for renewable
energy technologies), telecommunication infrastructure,
transistor gate dielectrics, and consumer battery applications
(cell phones, computers, etc.).
Research for longer lasting batteries has been an
ongoing process for years. Researchers have now begun to
utilize nanotechnology for battery techno to alter the wetting
behavior of the surface where the liquid in the battery lies to
spread the liquid droplets over a greater area on the surface
and therefore have greater control over the movement of the
droplets.
This gives more control to the designer of the battery. This
control prevents reactions in the battery by separating the
electrolytic liquid from the anode and the cathode when the
battery is not in use and joining them when the battery is in
need of use.
A phosphor, most generally, is a substance that exhibits
the phenomenon of luminescence. Somewhat confusingly,
this includes both phosphorescent materials, which show a
slow decay in brightness (> 1 ms), and fluorescent materials,
where the emission decay takes place over tens of
nanoseconds. Phosphorescent materials are known for their
use in radar screens and glow-in-the-dark toys, whereas
fluorescent materials are common in cathode ray tube (CRT)
and plasma video display screens, sensors, and white LEDs.
Sunscreens made with zinc oxide and titanium dioxide are
better because:
1) they provide strong sun protection with few health
concerns;
2) they don’t break down in the sun;
3) zinc oxide offers good protection from UVA rays – titanium
oxide less so, but better than most other active ingredients.
Nanosensors are any biological, chemical, or surgical sensory
points used to convey information about nanoparticles to
the macroscopic world. Their use mainly include various
medicinal purposes and as gateways to building other
nanoproducts, such as computer chips that work at the
nanoscale and nanorobots. Presently, there are several ways
proposed to make nanosensors, including top-down
lithography, bottom-up assembly, and molecular selfassembly.
Medicinal uses of nanosensors mainly revolve around the
potential of nanosensors to accurately identify particular cells
or places in the body in need. By measuring changes
in volume, concentration, displacement and velocity, gravitati
onal, electrical, and magnetic forces, pressure,
or temperature of cells in a body, nanosensors may be able to
distinguish between and recognize certain cells, most notably
those of cancer, at the molecular level in order to deliver
medicine or monitor development to specific places in the
body. In addition, they may be able to detect macroscopic
variations from outside the body and communicate these
changes to other nanoproducts working within the body.