Tag: nanotechnology

The bulk modulus of single walled phase nanotubes is 462 to 546 GPa, even higher than that of diamond (420 GPa for single diamond crystal). This is because chemical bonding of nanotubes involves entirely $sp^{2}$ hybrid carbon atoms. These bonds, which are similar to those of graphite and are stronger than diamond (which employ $sp^{3}$ hybrid carbon atoms), this provides nanotubes with their unique strength.

Nanotechnology uses:

1. Medicine: for chemotherapy and anti-ageing drugs
2. Used in 3D printing
3. Super fluidity at high temperature.

STM: Scanning Tunneling Microscope.
It is an instrument for imaging surfaces at the atomic level. It is based on the concept of Quantum tunneling. When a conducting tip is brought very near to surface to be examined, a potential difference applied between two can allow electrons to tunnel through the vacuum between them.

A paper battery is a battery made using a paper-thin sheet of cellulose infused with aligned carbon nano-tubes. It acts as a high energy battery. It provides long term, steady power production and burst of energy. These batteries are non-toxic, flexible and used in electronic, medical devices and new technologies.

Cylindrical fullerenes are also called carbon nanotubes or buckytubes. These are a form of carbon similar to graphite found in pencils. They are hollow cylindrical tubes and are 10,000 times smaller than a human hair.

1. Fullerene is another form of carbon allotropes.
   2. It can be identified as $C-60$ since, it is made of $60$atoms, arranged in the shape of a football.
   3. Since, this look like the geodesic dome designed by the US archited Buckminster Fuller, the molecule was named Fullerence.

Ultrahard Fullerites are made under high pressure 13 GPa and require high temperature for heating up to 1100 K (more than 820°C).

Size of Red Blood Cells is around 6 to 8 microns. 
i.e. $6-8\times10^{-6}$ m.
So, out of options available, 5000 nm or 5 μm lies near this range. So answer is 5000 nm.

Size of Nanoparticles lies in the range of 1 to 100 nm

Quantum dot is a Semi conductor made up of Nano particles.Basically a single electron trapped inside a cage of atoms and when the dot is exposed to a pulse of light at the right time and wavelength, the electron is raised to an exited state. Thus when the electron fall back to its ground state, these dots then have the ability to glow. Quantum dots are a special class of materials known as semiconductor. Quantum dots are very special because they are so small that 4,000,000 dots take up 2 cm. Hence option C is correct.