1 Summary Science and Technology Class 08 ## Multiple choice question discussion from the topics covered in the previous class (5:08 PM) ## The uniqueness of Nanotechnology (continued)(5:37 PM) - (c) Most of the biology occurs at the nanoscale. For example, Haemoglobin has a 5 nm diameter, and DNA molecule 2 nm diameter. - Medical researchers are working on designing tools, treatments, and therapies that are more precise, with the help of nanotechnology. - (d) Nanomaterials exhibit phenomena of self-assembly. - Self-assembly describes the process in which a group of components forms an ordered structure driven by mutual interactions. ## Nanomanufacturing (5:49 PM) - There are mainly two approaches to making nanomaterials - (a) ==Top-down approach== - A large piece of material is reduced all the way down to the nanoscale. - This leads to wastage. - Surface characteristics cannot be controlled. - But it is simpler and cheaper. - (b) ==Bottom-up approach== - It creates products building them atom-by-atom, molecule-by-molecule. - It can be time-consuming, and expensive but surface characteristics can be regulated. ## Dimensionality of Nanomaterials (6: 00 PM) - Nanomaterials can have zero dimensions. It means that all dimensions are at the nanoscale. For example, Quantum dots - ==One-dimension== - In two dimensions it is at the nanoscale. In the third direction, it is at the macroscale. For example, Nanotubes - ==Two-dimension== - It is at the nanoscale, only in one direction. In the other two directions, it is at the macroscale. For example, Thin Films - ==3-D bulk nanomaterial== - All dimensions are at the macro scale. For example, polycrystals ## Applications of Nano Technology (6:11 PM) - ==Daily life applications== - (a) Nanoscale additives can make fabric acquire properties such as anti-wrinkling, anti-staining, or even inhibit bacterial growth. - (b) Nanoscale films on eyeglasses and displays, make them anti-reflective, scratch-resistant, water-repellent, etc. - (c) Lightweighting of automobiles - Lightweighting of automobiles with the help of nanomaterials can make them more energy efficient. - (d) Cosmetics- sunscreen lotions, lipsticks, etc. - ==Applications in Healthcare== - (a) ==Cancer Treatment== - Certain nanomaterials such as gold have proven to be effective in destroying a tumour. - (b) ==Targeted drug delivery== - A nanoparticle can encapsulate or otherwise help to deliver medication directly to diseased tissues. - This reduces the side effects of the medicines. - (c) ==Gene Editing== - Gene editing requires precision, and many gene editing techniques use nanomaterials to attain such precision. - (d) ==Vaccines== - Researchers are looking at ways that how nanotechnology can improve vaccines, including their delivery. - (e) ==Anti-microbial resistance== - When microbial organisms such as bacteria, viruses, protozoans, etc develop resistance against the very medicine that we take to kill them, it is called anti-microbial resistance. - For example, antibiotic-resistant bacteria. - Researchers have found out that certain nanomaterials such as quantum dots are very effective at killing such bacteria. ## Application in electronics ## (6:59 PM) - (a) Flexible, foldable, and bendable displays are possible because of nanotechnology. - (b) Ultra-high-definition display in televisions with the help of quantum dots. - Quantum dots or QLED displays are more energy efficient compared to other displays. - (c) Transistors, basic switches that enable all modern computing have become smaller and smaller with the help of nanotechnology. - ==Applications in the environment== - (a) For water filtration, nano-membrane has proven to be more effective than conventional filters. - (b) To control air pollution, certain changes have been introduced in the engines of automobiles, or in thermal power plants, which is facilitated by nanotechnology. - (c) Similarly to tackle oil spills, researchers are using water-repellent nanoparticles. ## Carbon nanotubes (7:11 PM) - Carbon nanotubes are cylindrical molecules that consist of a single layer of carbon atoms called graphene. - Graphene in itself is an amazing nanomaterial, known for high thermal and electrical conductivity, and high tensile strength, despite being lighter than steel. - Carbon nanotube acquires some of these properties but depending on how we are folding, the size, and the number of layers, they can acquire different properties. - For example, a carbon nanotube can be a conductor or semiconductor. - The hollow part of the carbon nanotube can be filled with nanomaterials. - These nanomaterials will be separated and shielded from their surroundings. - Because of these properties, carbon nanotubes have applications in many areas such as electronic devices, lithium-ion batteries, hydrogen storage cells, and biosensors among others. ## Quantum Dots (7:36 PM) - Quantum dots are nanoscale semiconductors. - They can emit light of various colours, just by changing their size. - Their potential application includes solar cells, medical imaging, and quantum computing. - They already have applications in display technology. ## Nanotechnology in India (7:38 PM) - (1)National Mission on nanoscience and technology - Nano Mission was launched in 2007 under the Department of Science and Technology. - The first phase was in 2007-12, and the second phase was in 2014-20. - ==Objectives== - (a) basic research promotion in Nanotechnology - (b) Infrastructure development in the research institutes. - (c) International Collaboration - (d) Private sector participation - (e) Human Resource Development - (f) Using nanotechnology to solve the issues being faced by India. - (2) The Ministry of Electronics and Information Technology has a Nanotechnology initiative division, which is working on developing indigenous products in the electronics sector. - It is being implemented with the help of IIsc Bengaluru and IIT Bombay. - (3) Nano urea - IIFCO (Indian Farmers Fertiliser Cooperative Limited) has developed a new fertilizer called nano urea, which is a nanoparticle of nitrogen in a stable form. - Typically, one bag of urea contains 45 kg of fertilizer, which has about 20 kg of nitrogen. - This one bag can be replaced with 500ml of nano urea, which has about 20 grams of nitrogen. - Because of increased surface area, nano urea is more reactive and can be absorbed directly by the stomata of plants. - Thus, overall urea consumption reduces, which has environmental benefits. - Also, the government can reduce the burden of fertilizer subsidies which has economic benefits. ## The topics for the next class: Concerns with Nanotechnology, Information, and computing technology.