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Comment by Dr. Krishna Kumari Challa on December 21, 2013 at 8:16am

Scientists Discover New Surprising Details About Table Salt
An international team of scientists has discovered a surprise hidden in the first chemical compound that children learn about: table salt.

Under certain high pressure conditions, table salt, scientifically known as sodium chloride, can take on some surprising forms that violate standard chemistry predictions. The findings, published in Science, may hold the key to answering lingering questions about planet formation.

The researchers used advanced algorithms to predict an array of possible stable structural outcomes that would result from compressing rock salt. Using a diamond anvil at DESY’s X-ray source PETRA III, they put the salt under high pressure of 200,000 atmospheres. They added an extra “dash” of either sodium or chlorine, creating new “forbidden” compounds like Na3Cl and NaCl3.
Such compounds require a completely different form of chemical bonding with higher energy. Because nature always favors the lowest state of energy, such compounds should not happen.
These compounds are thermodynamically stable and once made, remain so indefinitely,” says Zhang. “Classical chemistry forbids their very existence. Classical chemistry also says atoms try to fulfil the octet rule – elements gain or lose electrons to attain an electron configuration of the nearest noble gas, with complete outer electron shells that make them very stable. Well, here that rule is not satisfied.”

The results of these experiments help to explore a broader view of chemistry. “I think this work is the beginning of a revolution in chemistry,” Oganov says. “We found, at low pressures achievable in the lab, perfectly stable compounds that contradict the classical rules of chemistry. If you apply rather modest pressure, 200,000 atmospheres – for comparison purposes, the pressure at the centre of the Earth is 3.6 million atmospheres – much of what we know from chemistry textbooks falls apart.”

“Here on the surface of the earth, these conditions might be default, but they are rather special if you look at the universe as a whole,” Konôpková explains. What may be “forbidden” under ambient conditions on earth, can become possible under more extreme conditions.
This discovery could lead to new, practical applications, say the researchers.

“When you change the theoretical underpinnings of chemistry, that’s a big deal,” Goncharov says. “But what it also means is that we can make new materials with exotic properties.”

Among the compounds Oganov and his team created are two-dimensional metals, where electricity is conducted along the layers of the structure.

“One of these materials – Na3Cl – has a fascinating structure,” Oganov says. “It is comprised of layers of NaCl and layers of pure sodium. The NaCl layers act as insulators; the pure sodium layers conduct electricity. Systems with two-dimensional electrical conductivity have attracted a lot interest.”

The research team hopes that the table salt experiments will only be the beginning of the discovery of completely new compounds. “If this simple system is capable of turning into such a diverse array of compounds under high-pressure conditions, then others likely are, too,” Goncharov explains. “This could help answer outstanding questions about early planetary cores, as well as to create new materials with practical uses.”

http://www.redorbit.com/news/science/1113033114/salt-chemistry-surp...

Comment by Dr. Krishna Kumari Challa on December 20, 2013 at 8:00am

Dog dust may benefit infant immune systems
Microbes from pet-owning houses protected mice against allergy, infection

https://www.sciencenews.org/article/dog-dust-may-benefit-infant-imm...

Comment by Dr. Krishna Kumari Challa on December 20, 2013 at 7:59am

Ancient bond holds life together, literally
Animal tissues and organs may require a specific link between sulfur and nitrogen
The rise of multicellular structures in animals may have hinged on a chemical link between sulfur and nitrogen atoms.

In animal tissues and organs, cells lock into a scaffold of collagen proteins that allows the cells to stick together and coordinate activities, such as tissue repair. Sulfur-nitrogen connections called sulfilimine bonds form essential links that keep the protein scaffold together, researchers have now discovered.

https://www.sciencenews.org/article/ancient-bond-holds-life-togethe...

Comment by Dr. Krishna Kumari Challa on December 20, 2013 at 7:57am

Nicotine may damage arteries
Other chemicals in cigarettes may not be to blame
Even smokeless cigarettes may cause damage that can lead to hardening of the arteries, a new study implies.

Vascular smooth muscle cells wrap around blood vessels and help control blood flow and pressure. But inflammation and chemicals, such as those found in cigarette smoke, can turn the cells into miniature drills that chew through connective tissue, allowing muscle cells to burrow into blood vessels. Once inside, the cells and other debris clump into artery-clogging plaques.

Nicotine is one chemical that helps turn normal muscle cells into invaders...
https://www.sciencenews.org/article/nicotine-may-damage-arteries

Comment by Dr. Krishna Kumari Challa on December 20, 2013 at 7:57am

Nicotine may damage arteries
Other chemicals in cigarettes may not be to blame
Even smokeless cigarettes may cause damage that can lead to hardening of the arteries, a new study implies.

Vascular smooth muscle cells wrap around blood vessels and help control blood flow and pressure. But inflammation and chemicals, such as those found in cigarette smoke, can turn the cells into miniature drills that chew through connective tissue, allowing muscle cells to burrow into blood vessels. Once inside, the cells and other debris clump into artery-clogging plaques.

Nicotine is one chemical that helps turn normal muscle cells into invaders...
https://www.sciencenews.org/article/nicotine-may-damage-arteries

Comment by Dr. Krishna Kumari Challa on December 20, 2013 at 7:31am

Comment by Dr. Krishna Kumari Challa on December 20, 2013 at 7:27am

http://www.newscientist.com/special/reality?cmpid=NLC|NSNS|2013-1219-GLOBAL&utm_medium=NLC&utm_source=NSNS&

What is reality - a series of articles on reality

Comment by Dr. Krishna Kumari Challa on December 20, 2013 at 7:14am

Human Exposure to Possibly Neurotoxic Pesticides Should Be Reduced, E.U. Safety Agency Recommends

Two neonicotinoids, a class of insecticide linked to bee declines and to disruptions to rat neurons, "may affect the developing human nervous system," the safety agency states
http://www.scientificamerican.com/article.cfm?id=human-exposure-to-...

Comment by Dr. Krishna Kumari Challa on December 19, 2013 at 8:54am

Comment by Dr. Krishna Kumari Challa on December 19, 2013 at 8:43am

Glaxo Says It Will Stop Paying Doctors to Promote Drugs
The British drug maker GlaxoSmithKline will no longer pay doctors to promote its products and will stop tying compensation of sales representatives to the number of prescriptions doctors write, its chief executive said Monday, effectively ending two common industry practices that critics have long assailed as troublesome conflicts of interest.
http://www.nytimes.com/2013/12/17/business/glaxo-says-it-will-stop-...;

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