Thursday, March 31, 2011

Bananas Could Make Cars Leaner, Greener

Source

Updated: Additional information from Alcides Leão was added to this story March 28 at 8:05 p.m. EDT.

Researchers are going bananas in the quest to build cleaner, greener cars.

Brazilian scientists have developed a way of using fibers from bananas, pineapples and other plants to create plastic that is stronger and lighter than the petroleum-based stuff. So-called nanocellulose fibers rival Kevlar in strength but are renewable, and the researchers believe they could be widely used within a couple of years.

“The properties of these plastics are incredible,” Alcides Leão, a researcher at Sao Paulo State University, said in a statement. “They are light, but very strong — 30 percent lighter and three to four times stronger.”

That could reduce the weight of new vehicles, which would increase fuel economy. Several automakers are cutting weight in their campaigns to maximize mpg. Ford, for example, hopes to trim 250 to 750 pounds from its vehicles and is exploring nanotechnology to do so.

Beyond being lighter and stronger, Leão says nanocellulosic plastic is more resistant to heat, gasoline and water. He sees it being used for dashboards, bumpers and some body panels.

Cellulose comprises the primary cell wall of green plants. Intensive processing of wood and other plant materials yields nanocellulosic fibers so small that 50,000 fit within the diameter of a human hair. These fibers can be added to other raw materials to produce reinforced plastic.

Leão tells us the nanocellulosic plastic is made entirely of renewable materials and is biodegradable. The nanocellulose could be combined with petroleum-based plastic if a specific application required it, he says, but the resulting product would not be biodegradable.

Pineapple may be the most promising source of nanocellulose, Leão says. Others include bananas, coconut shells, agave and curaua, a plant related to pineapple. The leaves and stems are cooked in a device similar to a pressure cooker, yielding something resembling talcum powder.

It’s expensive stuff, but there’s no word on just how much the nanocellulosic plastic costs because Leão and his team are working in small quantities in the laboratory. Leão says the cost would come down as the scale of production rose, especially if the auto industry embraced the technology. One pound of nanocellulose can produce 100 pounds of plastic.

“So far, we’re focusing on replacing automotive plastics,” Leão says. “But in the future, we may be able to replace steel and aluminum automotive parts using these plant-based nanocellulose materials.”

Leão presented his findings today at the 241st National Meeting & Exposition of the American Chemical Society in Anaheim, California.

Wednesday, March 30, 2011

Earth's Second Moon

Discovery

Cruithne was discovered on October 10, 1986, by Duncan Waldron on a photographic plate taken with the UK Schmidt Telescope at Siding Spring Observatory, Coonabarabran, Australia. The 1983 apparition (1983 UH) is credited to Giovanni de Sanctis and Richard M. West of the European Southern Observatory in Chile. It was not until 1997 that its unusual orbit was determined by Paul Wiegert and Kimmo Innanen, working at York University in Toronto, and Seppo Mikkola, working at the University of Turku in Finland.

The asteroid is named after the Cruithne or Cruthin, a people of early medieval Ireland.[3]

Dimensions and orbit

Cruithne is approximately 5 kilometres (3.1 mi) in diameter, and its closest approach to Earth is approximately thirty times the separation between Earth and the Moon (12 Gm or twelve million kilometres). From 1994 through 2015, Cruithne makes its annual closest approach to Earth every November.[4] Although Cruithne's orbit is not thought to be stable over the long term, calculations by Wiegert and Innanen showed that it has probably been synchronized with Earth's orbit for a long time. There is no danger of a collision with Earth for millions of years, if ever. Its orbital path and Earth's do not cross, and its orbital plane is currently tilted to that of the Earth by 19.8°. Cruithne, having a maximum near-Earthmagnitude of +15.8, is fainter than Pluto and would require at least a 12.5-inch (320 mm) reflecting telescope to be seen.[5][6]

Cruithne is in a normal elliptic orbit around the Sun. Its period of revolution around the Sun, approximately 364 days at present, is almost equal to that of the Earth. Because of this, Cruithne and Earth appear to "follow" each other in their paths around the Sun. This is why Cruithne is sometimes called "Earth's second moon".[2] However, it does not orbit the Earth and is not a moon.[7] In 2058, Cruithne will come within 0.09 AU (13.6 million kilometres) of Mars.[4] Cruithne's distance from the Sun and orbital speed vary a lot more than the Earth's, so from the Earth's point of view Cruithne actually follows a kidney bean-shaped horseshoe orbit ahead of the Earth, taking slightly less than one year to complete a circuit of the "bean". Because it takes slightly less than a year, the Earth "falls behind" the bean a little more each year, and so from our point of view, the circuit is not quite closed, but rather like a spiral loop that moves slowly away from the Earth.

After many years, the Earth will have fallen so far behind that Cruithne will then actually be "catching up" on the Earth from "behind". When it eventually does catch up, Cruithne will make a series of annual close approaches to the Earth and gravitationally exchange orbital energy with Earth; this will alter Cruithne's orbit by a little over half a million kilometres (whilst Earth's orbit is altered by about 1.3 centimetres (0.51 in)) so that its period of revolution around the Sun will then become slightly more than a year. The kidney bean will then start to migrate away from the Earth again in the opposite direction — instead of the Earth "falling behind" the bean, the Earth is "pulling away from" the bean. The next such series of close approaches will be centred on the year 2292 — in July of that year, Cruithne will approach Earth to about 12,500,000 kilometres (7,800,000 mi).

After 380 to 390 years or so, the kidney-bean-shaped orbit approaches Earth again from the other side, and the Earth, once more, alters the orbit of Cruithne so that its period of revolution around the Sun is again slightly less than a year (this last happened with a series of close approaches centred on 1902, and will next happen with a series centered on 2676). The pattern then repeats itself.


Cruithne appears to make a bean-shaped orbit from the perspective of Earth


Cruithne and Earth seem to follow each other in their orbits

Sunday, March 27, 2011

Tuesday, March 22, 2011

Sunday, March 13, 2011

Japan Earthquake Predicted. Comet Elenin?

"Comet Elenin, Earth, and the Sun were in exact alignment last year on February 27th. That is when the Chile Earthquake happened, and Earth's axis shifted. This year, the same alignment happens March 11-15, and the comet is much closer. PLEASE move away from fault areas during this time!"

Saturday, March 12, 2011

Scientists Use Sunlight to Make Fuel From CO2

By Chuck Squatriglia Email 01.04.08
Sandia researcher Rich Diver checks out the solar furnace which will be the initial source of concentrated solar heat for converting carbon dioxide to fuel. Eventually parabolic dishes will provide the thermal energy.
Photo: Randy Montoya / Sandia National Laboratories

Researchers at Sandia National Laboratories in New Mexico have found a way of using sunlight to recycle carbon dioxide and produce fuels like methanol or gasoline.

The Sunlight to Petrol, or S2P, project essentially reverses the combustion process, recovering the building blocks of hydrocarbons. They can then be used to synthesize liquid fuels like methanol or gasoline. Researchers said the technology already works and could help reduce greenhouse-gas emissions, although large-scale implementation could be a decade or more away.

"This is about closing the cycle," said Ellen Stechel, manager of Sandia's Fuels and Energy Transitions department. "Right now our fossil fuels are emitting CO2. This would help us manage and reduce our emissions and put us on the path to a carbon-neutral energy system."

The idea of recycling carbon dioxide is not new, but has generally been considered too difficult and expensive to be worth the effort. But with oil prices exceeding $100 per barrel and concerns about global warming mounting, researchers are increasingly motivated to investigate carbon recycling. Los Alamos Renewable Energy, for example, has developed a method of using CO2 to generate electricity and fuel.

S2P uses a solar reactor called the Counter-Rotating Ring Receiver Reactor Recuperator, or CR5, to divide carbon dioxide into carbon monoxide and oxygen.

"It's a heat engine," Stechel said. "But instead of doing mechanical work, it does chemical work."

Lab experiments have shown that the process works, Stechel said. The researchers hope to finish a prototype by April.

The prototype will be about the size and shape of a beer keg. It will contain 14 cobalt ferrite rings, each about one foot in diameter and turning at one revolution per minute. An 88-square meter solar furnace will blast sunlight into the unit, heating the rings to about 2,600 degrees Fahrenheit. At that temperature, cobalt ferrite releases oxygen. When the rings cool to about 2,000 degrees, they're exposed to CO2.

Since the cobalt ferrite is now missing oxygen, it snatches some from the CO2, leaving behind just carbon monoxide -- a building block for making hydrocarbons -- that can then be used to make methanol or gasoline. And with the cobalt ferrite restored to its original state, the device is ready for another cycle.

Fuels like methanol and gasoline are combinations of hydrogen and carbon that are relatively easy to synthesize, Stechel said. Methanol is the easiest, and that's where they will start, but gasoline could also be made.

However, creating a powerful and efficient solar power system to get the cobalt ferrite hot enough remains a major hurdle in implementing the technology on a large scale, said Aldo Steinfeld, head of the Solar Technology Laboratory at the Paul Scherrer Institut in Switzerland, in an e-mail.

He and Stechel said the technology could be 15 to 20 years from viability on an industrial scale.

The Sandia team originally developed the CR5 to generate hydrogen for use in fuel cells. If the device's rings are exposed to steam instead of carbon dioxide, they generate hydrogen. But the scientists switched to carbon monoxide, so the fuels they produce would be compatible with existing infrastructure.

Stechel said the Sandia team envisions a day when coal-fired power plants might have large numbers of CR5s, each reclaiming 45 pounds of carbon dioxide using reclamation technology currently under development and producing enough carbon monoxide to make 2.5 gallons of fuel. The Sunlight to Petrol process also raises the possibility that liquid hydrocarbon fuels might one day be renewable – provided CO2 reclamation reaches a point where the greenhouse gas can be snatched directly from the air. Such a process is being explored by Global Research Technologies and Klaus Lakner of Columbia University, among others.

Friday, March 4, 2011

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