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Showing posts from December, 2012

Carbon nanotube yarn, muscle and transparent sheets

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Carbon nanotubes
Carbon nanotubes (CNTs) have high strength and modulus, high electrical and thermal conductivities, are stable at relatively high and low temperatures. Individual nanotubes can be 100 times stronger than steel.
To effectively exploit the exceptional properties of individual nanotube’s in various applications, continuous pure CNT yarns and high CNT content composite yarns need to be fabricated.
MWCNTs reinforced PAN fibers and CNT/cellulosic continuous bamboo yarns can be used to manufacture CNTs filled multifunctional products by electro spinning. This process can give significant improvements of the mechanical, thermal and electrical properties of the yarn by incorporation of CNT into the nanofibers. SWCNT fibers can also be manufactured from liquid crystal solutions to get continuous neat CNT fibers.
Making CNT yarn
A continuous CNT fiber yarn using multiple threads of high purity double walled carbon nanotubes can be fabricated in a horizontal CVD gas flow reactor with …

3D- DNA nanostructures

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Folding the DNA DNA nanotechnology which is like paper folding was developed around 30 years back. In 2006, Paul Rothemund of the California Institute of Technology demonstrated folding long strands of DNA into a wide range of predetermined shapes. The resulting nanostructures can be used as scaffolding or as miniature circuit boards for precisely assembling components such as carbon nanotubes and nanowires. But to make DNA  structure of several folds, several hundred "staples" must be added to the regions surrounding the single DNA strands, and for making new nanostructures a new set of staples are requires. Moreover, the DNA structures tend to arrange themselves randomly onto a substrate surface making it difficult to integrate them into electronic circuits subsequently. DNA brick To overcome the above difficulty researchers at Harvard University in the US have developed a technique to make highly complex 3D nanostructures by assembling together synthetic DNA "bricks&qu…

Nanorod web to block light

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Nanorods
nanorods are one morphology of nanoscale objects with dimensions ranging from 1–100 nm. produced by direct chemical synthesis from metals or semiconducting materials. A combination of ligands acts as shape control agents bonding to different facets of the nanorod growing at different rates to produce elongated objects with desired strengths. The nanorods find application in MEMS, in energy harvesting and light emitting devices, as tunable photoluminescence and particularly in display technologies due to property that the reflectivity of the rods can be changed by changing their orientation with an applied electric field.
To make a new generation of optical devices such as light filters, sensors and other applications it is desirable to have a property by which it can be easily tuned with the interaction of light.
Web-like structure
Researchers at the Laboratory for Photonics and Nanostructures in Marcoussis, France have shown that a web-like structure made up of an array of eve…