Posted on 08 March 2010 by admin
A team of scientists at MIT has discovered a previously unknown phenomenon that can cause powerful waves of energy to shoot through minuscule wires known as carbon nanotubes, a discovery that could lead to a new way of producing electricity.
The phenomenon, described as thermopower waves, “opens up a new area of energy research, which is rare,” said Michael Strano, MIT’s Charles and Hilda Roddey Associate Professor of Chemical Engineering, who was the senior author of a paper describing the new findings.
Like a collection of flotsam propelled along the surface by waves traveling across the ocean, it turns out that a thermal wave — a moving pulse of heat — traveling along a microscopic wire can drive electrons along, creating an electrical current. The key ingredient in the recipe is carbon nanotubes — submicroscopic hollow tubes made of a chicken-wire-like lattice of carbon atoms.
In the new experiments, each of these electrically and thermally conductive nanotubes was coated with a layer of a highly reactive fuel that can produce heat by decomposing.
This fuel was then ignited at one end of the nanotube using either a laser beam or a high-voltage spark, and the result was a fast-moving thermal wave travelling along the length of the carbon nanotube like a flame speeding along the length of a lit fuse.
According to Strano, in the group’s initial experiments, when they wired up the carbon nanotubes with their fuel coating in order to study the reaction, “lo and behold, we were really surprised by the size of the resulting voltage peak” that propagated along the wire.
Posted on 02 March 2010 by admin
A team of scientists has discovered magnetic waves that fluctuate when exposed to certain conditions in a superconducting material.
The finding was made by Brown University physicist Vesna Mitrovic and colleagues at Brown and in France.
At the quantum level, the forces of magnetism and superconductivity exist in an uneasy relationship.
Superconducting materials repel a magnetic field, so to create a superconducting current, the magnetic forces must be strong enough to overcome the natural repulsion and penetrate the body of the superconductor. This relationship is pretty well known. But why it is so remains mysterious. Now, physicists at Brown University have documented for the first time a quantum-level phenomenon that occurs to electrons subjected to magnetism in a superconducting material.
They report that at under certain conditions, electrons in superconducting material form odd, fluctuating magnetic waves.
Posted on 19 February 2010 by admin
This traditional portrait of Athanasius Kircher gives his age as 76. The engraver has emphasized the energy in Kircher’s inquiring eyes. A professor of eloquence in Rome added the flowery inscription: “The painter or poet would declare only in error: ‘This is the man.’ But the farthest Antipodes know his name and face.”
Posted on 29 January 2010 by admin
Bird watchers walking along the beach on the Baltic island of Öland off Sweden’s southeastern coast were puzzled by an unusual natural phenomenon recently when they stumbled across dozens of football-sized balls of ice lying on the shore.
A week before Christmas, Magnus Bladh of the Ottenby bird station, located on Öland’s southern cape, was strolling along the beach with a colleague when he saw something he’d never seen before.
“Temperatures were below freezing and there was a light wind, but it was very cold! In the seaweed we noticed at least 200 large ice balls,” he said in a report to Swedish meteorological agency SMHI.
Posted on 15 September 2009 by admin
A research team from Indonesia’s Sam Ratulangi University, Indonesian Science Institution and Fukushima Aquamarine Japan once again found prehistoric fish called coelacanth at Talise waters of North Minahasa in 155 meter-depth.
The fish was found during the first hour of the researchers’ first day by a remotely operated vehicle (ROV).
Posted on 10 September 2009 by admin
Scientists and filmmakers have discovered a new species of giant rat deep in the jungle of Papua New Guinea along with other other animals hitherto unseen.
The woolly rat, an over-sized vegetarian rodent, measures 82 cm long and weighs in at 1.5 Kg. Its size makes it amongst the largest species of rat known anywhere in the world.
The creature was discovered by an expedition team filming for BBC program Lost Land of the Volcano.
Posted on 29 July 2009 by admin
When we talked with element 112’s discoverer, Sigurd Hofmann, on the significance of making a permanent mark on the periodic table, he told us he wanted a moniker that recognized a famous scientist while avoiding the flag-waving nationalism normally associated with the process. Today, Hofmann and his team made their decision public.
Good bye element 112 and ununbium, its placeholder name. Hello “Copernicium.”
By choosing to honor the father of the heliocentric solar system, element 112 discovery team leader Sigurd Hofmann wanted to avoid the divisive names selected for past elements, salute an influential scientist who didn’t receive any accolades in his own lifetime, and highlight the link between astronomy and Hofmann’s own field of nuclear chemistry.
Posted on 25 July 2009 by admin
Scientists at the Indian Institute of Science in Bangalore, along with researchers in Italy, have found two types of liquid water that have long been suspected to exist below water’s normal freezing point.
Unlike most liquids, water becomes less rather than more dense when it freezes — and it is densest not when it is coldest (at 0 degrees Celsius, just before it freezes) but at 4 degrees C.
These are just two of water’s host of anomalous properties, some of which are crucial to its behaviour in the natural environment.
In 1992, Gene Stanley of Boston University, Massachusetts, and his co-workers carried out computer simulations of water, which suggested that hydrogen bonds in water might produce two different types of liquid if water was made very cold and squeezed to high pressures.