Presentation on theme: "-DHYANA BAXI(13BEE032 -NEHA SAXENA(13BEE061). O Nanotechnology is the manipulation of matter with at least one dimension sized from 1 to 100 nanometers."— Presentation transcript:
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-to- diameter 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.
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 size- tunable 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 ultra- capacitor 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 self- assembly.
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.