 5. Hello everyone .. 6. Myself Dr. Ms. Tejaswice Rihanga Ghadge 7. working as an assistant professor in Department of Humanities & Science comple 8. in Department of Humanities & Science捂t 9. Volchene Institute of Technology, Sollapur 9 . I welcome all of you in the session of physics 10. Today we learnt about nanotechnology 11. In a previous session we saw the basic terms nanoscience, nanotechnology, nanomaterials, classification of nanomaterials, and the effect of surface-to-volume ratio and quantum confinement on nanomaterials. � tour, n ditch the study research of students who are able to understand the details of manastasional nanotubes,lassification of manastasional nanotubes and the applications of nanotechnology in various departments n changing hype. ҉ that true in the development of nontransvestible nanotubes , e ҉ that social nanotubes 11. Their structure is similar to fullerine, but while the fullerine's molecules forms a spherical shape, the nanotubes are cylindrical in structure with the ends covered by a half fullerine molecule. nanotube diameter is of the order of few nanometers, while their length can be of order of several millimeters. The physical properties of nanotubes in nanometric scale shows the unusual strength, unique electrical properties and extremely high thermal conductivity, carbon nanotubes. There are three forms of carbon that is diamond, graphite and amorphous carbon and other form of carbon known as carbon nanotube which is related to graphite. The molecular structure of graphite is one atom thick, a planar network of interconnected hexagonal rings of carbon atoms. In graphite, the sheets of carbon are stacked on top of one another and they can easily slide over each other. Hence, graphite is not hard but used as a lubricant. When graphite sheets are rolled into a cylinder and join their edges, then carbon nanotubes were formed. That is, carbon nanotubes are the extended tubes of rolled graphite sheets arranged in a hexagonal manner. Hexagonal structure provides tensile strength, elastic properties, length is 100 micrometer, diameter approximately 2 nanometer. It is 600 times stronger than still and 6 times lighter than it. Now, let us see classification of carbon nanotubes. Carbon nanotubes are classified as single-walled carbon nanotubes and multi-walled carbon nanotubes. Single-walled carbon nanotubes are long-wrapped graphite sheets. The fundamental cylindrical structure which forms the building block of both multi-walled carbon nanotubes and single-walled carbon nanotubes. Diameter varies 1 nanometer to 5 nanometer, length 1 millimetre, length to diameter ratio 1000. So, it is one-dimensional structure. The multi-walled carbon nanotubes has coaxial layers which form the tube-like structure. Each multi-walled carbon nanotubes has 2 to 50 tubes. Inner diameter varies from 1.5 to 15 nanometer, outer diameter 2.5 to 30 nanometer and length 1 millimetre. Multi-walled carbon nanotubes has a more complex array of a form. Each concentric multi-walled carbon nanotubes has different structures and hence there are variety of sequential arrangements. The simplest sequence is when concentric layers are identical but differ in diameter. Carbon nanotubes are arranged in different orders. These can have either regular layering or random layering. The structure of nanotubes influences electrical, thermal conductivity, density and lattice structure. In both the type, single-walled carbon nanotubes and multi-walled carbon nanotubes, diameter of carbon nanotubes are very important. Wider the diameter of nanotubes is behaves like a graphite and narrower the diameter of nanotubes it has some specific properties. Carbon nanotubes have their novel chemical and physical properties. That is mechanically they are very strong, flexible and can conduct more electricity. The helicity of the graphite sheet determines whether the carbon nanotubes is a semi-conductor or metallic. All the remarkable properties of carbon nanotubes have potential application in composites, sensor, nano-electronics and display devices. Carbon nanotubes has a variety of diameters, lengths and functional group content. They are also available for industrial applications in bulk. Now depending upon the folding of graphite sheet, carbon nanotubes are classified as armchair, zigzag and chiral. It is possible to recognize these type by analyzing their cross-sectional structure. Let us see in detail one by one. Armchair, these are formed for the angle theta is equal to pi by six and chirality aa. Armchair structure with arrangement of carbon atoms is as shown in figure, the zigzag arrangement. These are formed for the angle theta is equal to zero, chirality a zero that means it form by folding parallel to x axis. Zigzag arrangement of carbon is shown in figure. These tubes are chiral tubes that is their mirror images are similar as the original structure. Chiral, these are obtained when angle theta is in between zero to pi by six and chirality a b. These tubes are chiral that is mirror images are appear to differ from their original structure. The table shows comparison between different types of carbon nanotubes. Think for a while can you tell any field where we can use nanotechnology. Now let us see the applications of nanotechnology in the various fields. In electronics, nanotechnology increases the capabilities of electronic devices by reducing their weight and increases in power consumption. In the field of energy, it is used to develop clean, affordable and renewable energy sources to reduce their energy consumption and less toxicity environment. The wires will have much lower resistance than the high tension wires which are currently used in the electric grid. It reduces transmission power loss. Nanostructured solar cells could be cheaper to manufacture and easier to install. It is used to develop many new kinds of batteries that are quicker charging, more efficient, lighter in weight, have a higher power density and can hold good electrical charge in the field of automobiles. It includes high power rechargeable battery, thermoelectric material for the temperature control, lower rolling resistance tires, high efficiency and low cost sensors, fuel additives and improved catalytic converters for cleaner exhaust and extended range in field of space. Nanomaterial makes lightweight spacecraft and cable for the space elevator. Significantly it reduces the amount of rocket fuel required for these advances and which lowers the cost of travelling in space. In the field of medical, nanomaterial advances the technology in medical tools and therapies which are currently used in the clinics. Nanomedicine gives the precise solution for disease, prevention, diagnosis and treatment in the field of environment. Nanomaterials are being used to clean industrial water pollutants through chemical reaction. Magnetic nanofibric tiny wires of potassium manganese oxide used to remove oil from the water in the field of textile. Nanofibers are water and strain repellent or wrinkle free garments. Nanotechnology has been utilized to incorporate small carbon particles into it and ensure surface assurance from electrostatic charges for the wearer. Now in the field of cosmetics use of titanium dioxide nanoparticle in sunscreen gives UV security and also whitening of the skin. These are the applications of nanotechnology in the various fields. These are the references. Thank you.