Presentation on Nanotechnogy

8/2/2019 Presentation on Nanotechnogy

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Presentation on Nanotechnogy

Presented by,

Dilip PandeyShruti Pai

Siddharth Shinde


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What is Nanotechnology?

Nanotechnology is the study of manipulating matter

on an atomic and molecular scale. Generally,nanotechnology deals with developing materials,

devices, or other structures possessing at least one

dimension sized from 1 to100 nanometres.


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Environmental benefits of

nanotechnology

Energy

Nanotechnology could potentially have a

great impact on clean energy production.

Research is underway to use nanomaterials

for purposes including more efficient solar

cells, practical fuel cells, and environmentally

friendly batteries.


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Water filtration and remediation

A strong influence of nanochemistry on

waste-water treatment, air purification and

energy storage devices is to be expected.

Mechanical or chemical methods can be used

for effective filtration techniques. One class of

filtration techniques is based on the use of

membranes with suitable hole sizes, whereby

the liquid is pressed through the membrane.


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Impact of Nanotechnology

Nanopollution

Nanopollution is a generic name for all wastegenerated by nanodevices or duringthe nanomaterials manufacturing process. This kind of

waste may be very dangerous because of its size. It canfloat in the air and might easily penetrate animal andplant cells causing unknown effects. Most human-madenanoparticles do not appear in nature, so livingorganisms may not have appropriate means to deal

with nanowaste. It is probably one great challengeto nanotechnology: how to deal with itsnanopollutants and nanowaste.


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Bioaccumulation

Bioaccumulation refers to the accumulation ofsubstances, such as pesticides, or other organicchemicals in an organism.

Bioaccumulation occurs when an organismabsorbs a toxic substance at a rate greater thanthat at which the substance is lost. Thus, thelonger the biological half-life of the substance the

greater the risk of chronic poisoning, even ifenvironmental levels of the toxin are not veryhigh.


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Nanoparticles

Nanoparticles present possible dangers, both

medically and environmentally. Most of these

are due to the high surface to volume ratio,

which can make the particles very reactive

or catalytic. They are also able to pass

through cell membranes in organisms, and

their interactions with biological systems arerelatively unknown.


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Problems Life cycle

To properly assess the health hazards of

engineered nanoparticles the whole life cycle

of these particles needs to be evaluated,

including their fabrication, storage and

distribution, application and potential abuse,

and disposal. The impact on humans or the

environment may vary at different stages ofthe life cycle.


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The Royal Society report identified a risk of

nanoparticles or nanotubes being released

during disposal, destruction and recycling, andrecommended that manufacturers of

products that fall under extended producer

responsibility regimes such as end-of-liferegulations publish procedures outlining how

these materials will be managed to minimize

possible human and environmental exposure


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Inhalation: Inhaled particles induceinflammation in respiratory tract,

causing tissue damage. Example:Inhalation of silica particles inindustrial workers causes silicosis.

Ingestion: nanoparticles may cause liverdamage. Ingested nanoparticles (i.e. for

oral drug delivery) have been found toaccumulate in the liver. Excessiveimmune/inflammatory responses causepermanent liver damage.

Potential human hazards for nanoscale particulates.

Dermal exposure: Particles may enter

body through the skin. Potentialhazards are unknown at present.

Other: ocular, .

Adapted from presentation of Vicki Colvin, Rice University.


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Red- and green-emittingquantum dots highlight the

mitochondria and nuclei,respectively, of human epithelialcells in culture. Although thesecolorful nanocrystals don't seemto harm the cells, could theypose unforeseen hazards to

people or the environment?

Silica-coated semiconductor nanocrystals are readily incorporated into a wide variety of eukaryotic

cells.

In experiments where the quantum dots are deposited on a collagen substrate and then cells are

deposited on top of this, the cells incorporate any quantum dots that underlie them

When the cells migrate on a substrate, they ingest all the dots they pass over providing a convenientand rapid way for assessing the cells' potential to metastasize, or spread (as a cancer) from one part

of the body to another [Adv. Mater., 14, 882 (2002)].

The dots appear to go into cells as "inert spectators." The cells remain healthy and even continue to

divide, with each cell division reducing the number of dots in any given cell. The dots have no

discernible effect on the cells.

---- A. Paul Alivisatos

Semiconductor nanoparticules.

Presentation on Nanotechnogy

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