Download
1 / 12
E N D
The Meaning of Nanotechnology • When K. Eric Drexler (right) popularized the word 'nanotechnology' in the 1980's, he was talking about building machines on the scale of molecules, a few nanometers wide—motors, robot arms, and even whole computers, far smaller than a cell. Drexler spent the next ten years describing and analyzing these incredible devices, and responding to accusations of science fiction. Meanwhile, mundane technology was developing the ability to build simple structures on a molecular scale. As nanotechnology became an accepted concept, the meaning of the word shifted to encompass the simpler kinds of nanometer-scale technology. The U.S. National Nanotechnology Initiative was created to fund this kind of nanotech: their definition includes anything smaller than 100 nanometers with novel properties. • Much of the work being done today that carries the name 'nanotechnology' is not nanotechnology in the original meaning of the word. Nanotechnology, in its traditional sense, means building things from the bottom up, with atomic precision. This theoretical capability was envisioned as early as 1959 by the renowned physicist Richard Feynman. • I want to build a billion tiny factories, models of each other, which are manufacturing simultaneously. . . The principles of physics, as far as I can see, do not speak against the possibility of maneuvering things atom by atom. It is not an attempt to violate any laws; it is something, in principle, that can be done; but in practice, it has not been done because we are too big. — Richard Feynman, Nobel Prize winner in physics • Based on Feynman's vision of miniature factories using nanomachines to build complex products, advanced nanotechnology (sometimes referred to as molecular manufacturing) will make use of positionally-controlled mechanochemistry guided by molecular machine systems. Formulating a roadmap for development of this kind of nanotechnology is now an objective of a broadly based technology roadmap project led by Battelle (the manager of several U.S. National Laboratories) and the Foresight Nanotech Institute. • Shortly after this envisioned molecular machinery is created, it will result in a manufacturing revolution, probably causing severe disruption. It also has serious economic, social, environmental, and military implications.
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. 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. 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 [source: Berkeley Lab].
http://www.bbc.co.uk/learningzone/clips/nanotechnology-used-in-sunscreen-manufacture/6004.htmlhttp://www.bbc.co.uk/learningzone/clips/nanotechnology-used-in-sunscreen-manufacture/6004.html
A nanoparticle is a small object that behaves as a whole unit in terms of its transport and properties. Size of nanoparticles In terms of diameter, fine particles cover a range between 100 and 2500 nanometers, while ultrafine particles are sized between 1 and 100 nanometers. Nanoparticles may or may not exhibit size-related properties that are seen in fine particles. Despite being the size of the ultrafine particles individual molecules are usually not referred to as nanoparticles. Nanoclustershave at least one dimension between 1 and 10 nanometers and a narrow size distribution. Nano powders on the other hand are agglomerates of ultrafine particles, nanoparticles, or nanoclusters. Nano particle sized crystals are called nanocrystals.
As the wavelength of light is 400-700 nanometers, science did not possess microscopes capable of probing the 1-nanometer scale until the invention and refinement of the electron microscope. Electron microscopes use electrons rather than photons (light) to take images. Today's best electron microscopes have a resolution of just 0.05 nanometers, the diameter of a hydrogen atom. A nanometer is quite small, a billionth of a meter. It is 20 times wider than the diameter of a hydrogen atom. In terms of the electromagnetic spectrum, 1 nanometer is about the wavelength of soft x-rays. Hard x-rays and gamma rays have a shorter wavelength. The width of a DNA double-helix, the molecule that carries our genetic code, is about 2 nanometers. To get the length of a nanometer in perspective, pretend you were shrunk in size about 1.5 billion times, so your height become 1 nanometer. A human would be about 1.5 million km tall, from our new perspective. This is about 120 Earth diameters, or three times longer than the distance from the Earth to the Moon. Bacterial flagellum have a diameter of about 20 nanometers. Bacteria in general have a diameter between 300 and 5,000 nanometers. Members of the genus Mycoplasma, lacking a cell wall, are the smallest, at about 300 nanometer width.
http://www.bing.com/videos/search?q=nanometer&FORM=HDRSC3&adlt=strict#ahttp://www.bing.com/videos/search?q=nanometer&FORM=HDRSC3&adlt=strict#a
How many nanometers in 1 meters? The answer is 1000000000.We assume you are converting between nanometre and metre.You can view more details on each measurement unit:nanometers or metersThe SI base unit for length is the metre.1 metre is equal to 1000000000 nanometers, or 1 meters.Note that rounding errors may occur, so always check the results.Use this page to learn how to convert between nanometres and metres.Type in your own numbers in the form to convert the units!
Nano products • Where and how nanotechnologies are used now • This section provides an overview of the main areas where the various nanotechnologies are used in products which may be available in the UK now or in the near future. • It is not possible at this time to give a definitive list of the individual products available. This is because there isn't a centrally compiled list and it is not currently required that companies disclose how they are using the technology in their products. • We have focused some attention on the most commonly used areas, giving an overview of what nanotechnologies are used and where there are potentially safety concerns. • On the full site we hope to give more information on all these sectors and create a more comprehensive listing of brand names. The safety section will also be more comprehensive.
New properties, new issues The things that make nano so interesting also have implications for its safety. Because most nanomaterials behave differently than they do in their larger form, we need to find out more about their safety when they are used in these new ways. However, all nano materials are different, and need to be tested separately. As with ordinary materials, some nanomaterials will be more harmful than others and some may be appropriate to be used in one context, but not in others.
