-->
Drop Down MenusCSS Drop Down MenuPure CSS Dropdown Menu

Tuesday, October 18, 2011

The Discovery of "Quasicrystal" and Its Application

Scientists from Israel, Daniel Shechtman, won the Nobel Prize for chemistry in 2011 thanks to a remarkable discovery about how we understand the chemistry of solid materials differently. Scientists managed to break the old understanding of the patterns of crystal-forming component. In 1982, he found that the crystals do not always have an element forming the same pattern and repetitive (repetitive), but composed with a random pattern but dense. Discovery undermine long understood that said crystal has a repeating pattern forming. Years of research need to understand Shechtman's new truth recognized by scientists around the world. This discovery was initially rejected by the scientific community and even the chemistry of solid materials considered as something unnatural.
Israeli scientist Daniel Shechtman poses next to a transmission electron microscope at the Haifa Technion, Haifa, Israel, Wednesday, Oct. 5, 2011. Shechtman won the 2011 Nobel Prize in chemistry on Wednesday for his discovery of quasicrystals, a mosaic-like chemical structure that researchers previously thought was impossible. (Picture from: http://www.msnbc.msn.com/)
Daniel Shechtman phenomenal discovery is published in the authoritative journal Physical Review Letters with the title "Metallic Phase with Long Range Orientational Order and No Translation Symmetry" in 1984. In its publication, he said that guasicrystal is a material that shows resilience in a range far diffraction experiments and have no translational periodicity. In fact, the assumption that a crystal must be periodic in three dimensions has been challenged by a meeting of the modulated structure.
Quasicrystal pattern existing in the golden era of Islamic architecture in medieval. Development of the quasicrystal pattern until the pattern of findings Shechtman quasicrystal. (Picture from: http://news.discovery.com/)
Intermetalic quasicrystal is usually a hard and brittle materials with unusual transport properties and have very low surface energy. Thermal or heat transport in solid materials is usually enhanced by phonons and Bloch wave that develops as a consequence of the periodic nature of crystals. In a quasicrystal, the absence of collective transport modes result in behavior that is more like that found in glass than in a normal crystal. Quasicrystal low surface energy makes it resistant to corrosion and adhesion, and to produce a low friction coefficient.

Research on the quasicrystal further, more directed to the improvement of quasicrystal models that lead to the refinement of the position and shape of the surface atoms in five-dimensional space for the quasicrystal in axial positions, and six-dimensional space to form icosahedral crystals. A more detailed model and has a level of complexity that require large amounts of complex independent observations. To achieve this requires a long research because of the intensity distribution usually involves many variables.

Quasicrystal now successfully produced in the laboratory and developed into a powerful objects such as iron by several companies in Europe. Quasicrystal application for the manufacture of razor blades and small needle specifically for eye surgery. In addition, the quasicrystal is also being investigated to be able to generate electricity from thermal power. *** [YOHANIS NGILI | PIKIRAN RAKYAT 13102011]
Kindly Bookmark and Share it: