John Dalton-4

Northwestern scientists create chemical brain (8/29/2012)

Northwestern University scientists have connected 250 years of organic chemical knowledge into one giant computer network -- a chemical Google on steroids. This "immortal chemist" will never retire and take away its knowledge but instead will continue to learn, grow and share.

A decade in the making, the software optimizes syntheses of drug molecules and other important compounds, combines long (and expensive) syntheses of compounds into shorter and more economical routes and identifies suspicious chemical recipes that could lead to chemical weapons.

"It was realized that if they could link all the known chemical compounds and reactions between them into one giant network, we could create not only a new repository of chemical methods but an entirely new knowledge platform where each chemical reaction ever performed and each compound ever made would give rise to a collective 'chemical brain,'" said Bartosz A. Grzybowski, who led the work. "The brain then could be searched and analyzed with algorithms akin to those used in Google or telecom networks."

Called Chematica, the network comprises some seven million chemicals connected by a similar number of reactions. A family of algorithms that searches and analyzes the network allows the chemist at his or her computer to easily tap into this vast compendium of chemical knowledge. And the system learns from experience, as more data and algorithms are added to its knowledge base.

Details and demonstrations of the system are published in three back-to-back papers in the Aug. 6 issue of the journal Angewandte Chemie.

                                       -megha shrivastava

                                             roll no 27

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                                            CARBON NANOTUBES

Carbon nanotubes (CNTs) are allotropes of carbon with a cylindrical nanostructure. Nanotubes have been constructed with length-to-diameter ratio of up to 132,000,000:1, significantly larger than for any other material. These cylindrical carbon molecules have unusual properties, which are valuable for nanotechnology, electronics, optics and other fields of materials science and technology. In particular, owing to their extraordinary thermal conductivity and mechanical and electrical properties, carbon nanotubes find applications as additives to various structural materials. For instance, nanotubes form only a tiny portion of the material(s) in (primarily carbon fiber) baseball bats, golf clubs, or car parts.

Nanotubes are members of the fullerene structural family. Their name is derived from their long, hollow structure with the walls formed by one-atom-thick sheets of carbon, called graphene.

Applied quantum chemistry, specifically, orbital hybridization best describes chemical bonding in nanotubes. The chemical bonding of nanotubes is composed entirely of sp² bonds, similar to those of graphite. These bonds, which are stronger than the sp³ bonds found in alkanes and diamond, provide nanotubes with their unique strength.

                       

                                                  SURFACE CHEMISTRY                                                                 Speaking about the latest discoveries in chemistry, it is interesting to mention that the Nobel Prize in Chemistry for 2007 was awarded for substantial studies in surface chemistry, a science that is really important for the chemical industry. It improves understanding of a variety of processes, including iron rusting, fuel cells functioning and working of the catalysts in our cars.

Chemical reactions on catalytic surfaces are really important for a lot of industrial operations, including the production of artificial fertilizers. Surface chemistry can even provide explanation of the ozone layer destruction, with vital steps in the reaction taking place on the surfaces of small crystals of ice in the stratosphere. The semiconductor industry also greatly depends on knowledge of surface chemistry.

                                                                          

                                                                                      - AMRITA BASU

                                                                                          XI-B

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Radioactive Water: Tea Bags To The Rescue 

It has been five months since a deadly earthquake hit Japan, creating a nuclear disaster of frightening proportions. Within days, the water was contaminated with radioactive iodide, a contaminant that can present a serious health risk. Now, scientists here in the U.S believe they’ve found a new way to remove, not just radiation, but other potentially hazardous contaminants to make sure water is safe to drink.

Kitchen Chemistry

What do Wolfgang Puck and Top Chef, Richard Blais have in common? These chefs put pizzazz on the dinner plate by using something called molecular gastronomy. It’s a fancy way of saying they’re using science in the kitchen.

                                                         Syandita Malakar

                                       Roll No - 34