پاورپوینت آماده; What is nanotechnology

پاورپوینت آماده; What is nanotechnology

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What is nanotechnology? A Nanometer There are 1 billion (1,000,000,000) nanometers in 1 meter
There are 1 million (1,000,000) micrometers (or microns) in 1 meter
A line of ten hydrogen atoms lined up side by side is 1 nanometer long
Your finger nail grows 1 nanometer in 1 second
The diameter of your hair is approximately 50,000 nanometers
The abbreviation for nanometer is “nm”
Nanostructures/Nanomaterials Nanostructures are materials that, in at least one dimension, measure approximately 1 – 100 nm
Nanostructures or nanomaterials exhibit properties different from their macroscale counterparts (their “big brothers”) such as:
Mechanical strength (how hard they are to break)
Electrical conductivity (how fast electrons flow through them)
Thermal conductivity (how fast heat flows through them)
Chemical reactivity (how well/fast they react with other chemicals)
Transparency (how well you can see through them)
Magnetism (whether or not they are magnetic)
… and many more…
Microstructures, the cousin to nanostructures, typically measure between 100 nanometers and 100 micrometers in at least one dimension, but likely do not exhibit unique properties like nanostructures do

Types Of Nanostructures/Nanomaterials Nanoparticles or nanospheres: nanoscale lengths are measured in all three dimensions
Nanotubes or nanowires or nanorods: nanoscale lengths are measured in two dimensions only
Nanoscale thin films or ultra-thin films: nanoscale lengths are measured in one dimension only
Nanocomposites: a material comprised of many nanoscale inclusions (such as nanoparticles)
Nanostructured materials: a material that exhibits a unique structure that can be measured at the nanoscale Common Examples of Nanostructures/Nanomaterials Quantum dots: nanoparticles 2–10 nm in diameter, made from semiconductors, emit light in a specific wavelength range
Carbon nanotubes: hollow cylinders one to tens of nanometers in diameter, extremely strong (hard to break), conduct heat faster than any other known material
Buckyballs: nanoparticles comprised of exactly 60 carbon atoms (though there are other types), forming a network that resembles a soccer ball Why does this happen? Nanostructures obey the same fundamental laws of the universe as everything else in nature
But… some things that are negligible (can be ignored) at big scales cannot be ignored at small scales
For example:
Imagine you are an electron moving through a “big” copper wire 1 cm in diameter – you may never see the boundaries of the wire because you are so small compared to its diameter
Imagine you are an electron moving through a “small” copper wire 1 nm in diameter (more comparable to

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