About nano-particles?
• A nanoparticle (or nanopowder or nanocluster or nanocrystal) is a microscopic particle with at least one of its dimensions less than 100 nanometres (nm).
• One nanometre is a billionth of a metre. Typically, a nanoparticle would be about thousand times smaller than the tip of human hair.
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| What is so special about them? | These materials exhibit very different properties when they are reduced to nano-sizes.
For example, a nanoparticle of gold does not have golden colour. It exhibits very different colours depending on the size of the particle in the nano-range. So a 4 nm gold particle has a different colour than a 50 nm or a 200 nm gold particle, and none of them is golden. Similarly, white gold, as we see it, melts at about 1100 degrees Celsius, while nanoparticles of gold can melt at 100 degrees Celsius. At nano-sizes, particles also start exhibiting some quantum properties, like super-paramagnetism. Quantum properties are associated with sub-atomic particles like electrons or neutrons that behave very differently than objects of sizes that we are familiar with. Such special properties open up a variety of possibilities for use of known materials for novel applications. |
| How to create nano-particles? | As of now, we create nanoparticles either by breaking down larger normal sized materials to nano size, or by assembling atoms or molecules in building-block fashion to reach nano sizes. |
| Applications in which fields? | Health, drug delivery, food processing, water purification, electronics, and many others. |
WORD FROM TEAM GS-SCORE –
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Science and technology of GS:3 |
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| For further detail | refer article titled “undermining the SYL canal” from TheHindu dated march 19, 2016 |