January 10, 2007 at 9:52 am
· Filed under Nanotechnology
Carbon nanotubes (CNTs) are an allotrope of carbon. They take the form of cylindrical carbon molecules and have novel properties that make them potentially useful in a wide variety of applications in nanotechnology, electronics, optics and other fields of materials science. They exhibit extraordinary strength and unique electrical properties, and are efficient conductors of heat. Inorganic nanotubes have also been synthesized.
Nanotubes are members of the fullerene structural family, which also includes buckyballs. Whereas buckyballs are spherical in shape, a nanotube is cylindrical, with at least one end typically capped with a hemisphere of the buckyball structure. Their name is derived from their size, since the diameter of a nanotube is on the order of a few nanometers (approximately 50,000 times smaller than the width of a human hair), while they can be up to several millimeters in length. There are two main types of nanotubes: single-walled nanotubes (SWNTs) and multi-walled nanotubes (MWNTs).
The nature of the bonding of a nanotube is described by applied quantum chemistry, specifically, orbital hybridization. Nanotubes are composed entirely of sp2 bonds, similar to those of graphite. This bonding structure, which is stronger than the sp3 bonds found in diamond, provides the molecules with their unique strength. Nanotubes naturally align themselves into “ropes” held together by Van der Waals forces.
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January 10, 2007 at 9:29 am
· Filed under Nanotechnology
There was a seminar today about Nanotechnology and its applications given by professor of Illunois University. The seminar was organized by Industrial Engineering Department of King Abdulaziz University after a conference at the Conference Hall on 9th January, 2007.
Many students from Engineering College (mostly from Industrial Engineering Department) participated and asked very good questions. I will not go in to detail about the seminar. However, I will mention the most important part which seemed very interesting to me. This point was raised by one of the panelists. It was very short but interesting idea.
It is about the Damascus Swords or Damascus Steel. As we know from the history, the Damascus Swords are very famous with sharpness and hardness as well as flexibility. We also know that Salahaddin Ayyubi won the battle against crusading Christian knights who were reclaiming Jerusalem from the Muslims. These damascus swords were containing nanotubes or nanotechnology according to the claim in seminar. I have made a quick search and found interesting articles about these Damascus Swords using Nanotechnology.
I hope you will find the compilation of articles useful. You can read from Nanotechnology used in Damascus Swords
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January 10, 2007 at 8:45 am
· Filed under Nanotechnology
Nanotechnology is a field of applied science and technology covering a broad range of topics. The main unifying theme is the control of matter on a scale smaller than one micrometre, as well as the fabrication of devices on this same length scale. It is a highly multidisciplinary field, drawing from fields such as colloidal science, device physics, and supramolecular chemistry. Much speculation exists as to what new science and technology might result from these lines of research. Some view nanotechnology as a marketing term that describes pre-existing lines of research.
Despite the apparent simplicity of this definition, nanotechnology actually encompasses diverse lines of inquiry. Nanotechnology cuts across many disciplines, including colloidal science, chemistry, applied physics, biology. It could variously be seen as an extension of existing sciences into the nanoscale, or as a recasting of existing sciences using a newer, more modern term. Two main approaches are used in nanotechnology: one is a “bottom-up” approach where materials and devices are built from molecular components which assemble themselves chemically using principles of molecular recognition; the other being a “top-down” approach where nano-objects are constructed from larger entities without atomic-level control.
The impetus for nanotechnology has stemmed from a renewed interest in colloidal science, coupled with a new generation of analytical tools such as the atomic force microscope (AFM) and the scanning tunneling microscope (STM). Combined with refined processes such as electron beam lithography, these instruments allow the deliberate manipulation of nanostructures, and in turn led to the observation of novel phenomena. Nanotechnology is also an umbrella description of emerging technological developments associated with sub-microscopic dimensions. Despite the great promise of numerous nanotechnologies such as quantum dots and nanotubes, real applications that have moved out of the lab and into the marketplace have mainly utilized the advantages of colloidal nanoparticles in bulk form, such as suntan lotion, cosmetics, protective coatings, and stain resistant clothing.
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