Wednesday, April 22, 2009

NANOTECHNOLOGY 1-billionth of a meter

INTRODUCTION
Nanotechnology refers to research on materials that are nanometer in size or about 1-billionth of a meter and applicable to virtually every technology and medicine.
HOW NANO TECHNOLOGY WORKS?
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.
WORLD OF NANOTECHNOLOGY
In order to understand the unusual world of nanotechnology, we need to get an idea of the units of measure involved. A centimeter is one-hundredth of a meter, a millimeter is one-thousandth of a meter, and a micrometer is one-millionth of a meter, but all of these are still huge compared to the nanoscale. A nanometer (nm) is one-billionth of a meter, smaller than the wavelength of visible light and a hundred-thousandth the width of a human hair.

As small as a nanometer is, it's still large compared to the atomic scale. An atom has a diameter of about 0.1 nm. An atom's nucleus is much smaller -- about 0.00001 nm. Atoms are the building blocks for all matter in our universe. You and everything around you are made of atoms. Nature has perfected the science of manufacturing matter molecularly. For instance, our bodies are assembled in a specific manner from millions of living cells. Cells are nature's nanomachines. At the atomic scale, elements are at their most basic level. On the nanoscale, we can potentially put these atoms together to make almost anything.
Semiconductors are with the right arrangement of atoms. Scientists are still working on finding ways to make carbon nanotubes a realistic option for transistors in microprocessors and other electronics.
PRODUCTS WITH NANOTECHNOLOGY
You might be surprised to find out how many products on the market are already benefiting from nanotechnology.
Sunscreens
Many sunscreens contain nanoparticles of zinc oxide or titanium oxide. Older sunscreen formulas use larger particles, which is what gives most sunscreens their whitish color. Smaller particles are less visible, meaning that when you rub the sunscreen into your skin, it doesn't give you a whitish tinge.





Self-cleaning glass
A company called Pilkington offers a product they call Active Glass, which uses nanoparticles to make the glass photo catalytic and hydrophilic. The photo catalytic 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
Clothing
Scientists are using nanoparticles to enhance your 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.
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.
Antimicrobial bandages - Scientist Robert Burrell created a process to manufacture antibacterial bandages using nanoparticles of silver. Silver ions block microbes' cellular respiration . In other words, silver smothers harmful cells, killing them.



Cleaners and disinfectants
EnviroSystems developed a mixture (called a nanoemulsion) of nano-sized oil drops mixed with a bactericide. The oil particles adhere to bacteria, making the delivery of the bactericide more efficient and effective.
New products incorporating nanotechnology are coming out every day. Wrinkle-resistant fabrics, deep-penetrating cosmetics, liquid crystal displays (LCD) and other conveniences using nanotechnology are on the market. Before long, we'll see dozens of other products that take advantage of nanotechnology ranging from Intel microprocessors to bio-nanobatteries, capacitors only a few nanometers thick. While this is exciting, it's only the tip of the iceberg as far as how nanotechnology may impact us in the future.
THE FUTURE OF NANOTECHNOLOGY
Nanotechnology may have its biggest impact on the medical industry. Patients will drink fluids containing nanorobots programmed to attack and reconstruct the molecular structure of cancer cells and viruses. There's even speculation that nanorobots could slow or reverse the aging process, and life expectancy could increase significantly.
Nanorobots could also be programmed to perform delicate surgeries.By working on such a small scale, a nanorobot could operate without leaving the scars that conventional surgery does. Additionally, nanorobots could change your physical appearance. They could be programmed to perform cosmetic surgery, rearranging your atoms to change your ears, nose, eye color or any other physical feature you wish to alter.



Nanotechnology has the potential to have a positive effect on the environment. For instance, scientists could program airborne nanorobots to rebuild the thinning ozone layer. Nanorobots could remove contaminants from water sources and clean up oil spills. Manufacturing materials using the bottom-up method of nanotechnology also creates less pollution than conventional manufacturing processes.
Our dependence on non-renewable resources would diminish with nanotechnology. Cutting down trees, mining coal or drilling for oil may no longer be necessary -- nanomachines could produce those resources.
Many nanotechnology experts feel that these applications are well outside the realm of possibility, at least for the foreseeable future. They caution that the more exotic applications are only theoretical. Some worry that nanotechnology will end up like virtual reality -- in other words, the hype surrounding nanotechnology will continue to build until the limitations of the field become public knowledge, and then interest will quickly dissipate.

Nanotechnology Challenges, Risks and Ethics

The most immediate challenge in nanotechnology is that we need to learn more about materials and their properties at the nanoscale. Universities and corporations across the world are rigorously studying how atoms fit together to form larger structures.
Because elements at the nanoscale behave differently than they do in their bulk form, there's a concern that some nanoparticles could be toxic. Some doctors worry that the nanoparticles are so small, that they could easily cross the blood-brain barrier, a membrane that protects the brain from harmful chemicals in the bloodstream. If we plan on using nanoparticles to coat everything from our clothing to our highways, we need to be sure that they won't poison us.
Closely related to the knowledge barrier is the technical barrier. In order for the incredible predictions regarding nanotechnology to come true, we have to find ways to mass produce nano-size products like transistors and nanowires. While we can use nanoparticles to build things like tennis rackets and make wrinkle-free fabrics, we can't make really complex microprocessor chips with nanowires yet.
There are some hefty social concerns about nanotechnology too. Nanotechnology may also allow us to create more powerful weapons, both lethal and non-lethal. Some organizations are concerned that we'll only get around to examining the ethical implications of nanotechnology in weaponry after these devices are built. They urge scientists and politicians to examine carefully all the possibilities of nanotechnology before designing increasingly powerful weapons.
Even so, nanotechnology will definitely continue to impact us as we learn more about the enormous potential of the nanoscale.
CONCLUSION
Nanotechnology is a boon for the upcoming scientists when used aptly.

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