Showing posts with label research. Show all posts
Showing posts with label research. Show all posts

Monday, November 5, 2007

FlashbacK : 50 Years Ago: The First Dog in Orbit


It's today :Research on space is showing the unlimited fortune of creation ,



Just a month after the Soviet Union stunned the world by putting the first artificial satellite into orbit, it boasted a new victory - a much bigger satellite carrying a mongrel dog called Laika.


The mission, 50 years ago Saturday, ended sadly for Laika but helped pave the way for human flight.


As with other episodes of the Soviet space program, Laika's mission was hidden under a veil of secrecy, and only after the collapse of the Soviet Union could the participants tell the real story behind it.


The satellite that carried Laika into orbit was built in less than a month in what was perhaps the world's fastest-prepared space mission ever.


Excited by the international uproar over the launch of Sputnik on Oct. 4, 1957, Soviet leader Nikita Khrushchev summoned Sergei Korolyov, the father of the Soviet space program, and ordered him to come up with "something new" to celebrate the Nov. 7 anniversary of the 1917 Bolshevik Revolution.


Khrushchev's demand was a shock even for Korolyov, whose team had managed to put together the first Sputnik in less than three months, said Georgy Grechko, a cosmonaut who started his career as a space engineer.


"We didn't believe that you would outpace the Americans with your satellite, but you did it. Now you should launch something new by Nov. 7," Korolyov quoted Khrushchev telling him, according to Grechko.


Boris Chertok, Korolyov's right-hand man, said the short notice made it impossible to design a principally new spacecraft, but there was also little sense in simply repeating the Sputnik launch.


"Korolyov rightly feared that this holiday gift could end up in an accident that would spoil a hard-won victory," Chertok wrote in his memoirs. But they couldn't argue with Khrushchev, and the decision to conduct the launch was made on Oct. 12.


When someone on Korolyov's team suggested putting a dog into orbit, he jumped at the idea.


Little was known about the impact of space flight on living things, and some believed they would be unable to survive the launch or the conditions of outer space.


The Soviet Union had experimented with launching dogs on short suborbital missions during ballistic missile tests, and some of them survived several such missions. All of them were stray mongrel dogs - doctors believed they were able to adapt quicker to harsh conditions - and all were small so they could fit into the tiny capsules.


Just nine days before the launch, Doctor Vladimir Yazdovsky chose one of them - 2-year-old Laika - for the mission.


Stories about how she was chosen vary. Some say Laika was chosen for her good looks - a Soviet space pioneer had to be photogenic. Others say space doctors simply had a soft spot for Laika's main rival and didn't want to see her die: Since there was no way to design a re-entry vehicle in time for the launch, the glory of making space history also meant a certain death.


"Laika was quiet and charming," Yazdovsky wrote in his book chronicling the story of Soviet space medicine. He recalled that before heading to the launchpad, he took the dog home to play with his children.


"I wanted to do something nice for her: She had so little time left to live," Yazdovsky said.


Working round-the-clock, Korolyov and his team combined a capsule that would carry the dog with basic life-support systems and elements of the first Sputnik. To simplify the design, they decided not to separate the satellite from the booster's second stage.


They worked without blueprints at a pace that was breathtaking even at the time of the space race and seems utterly impossible by today's standards.


"Now when we have computers, sophisticated industrial equipment, lasers and other things, no one is capable of making a new satellite in just one month," Grechko said in an interview. "Now it would take a month just to start doing the paperwork. Korolyov told us later that it was the happiest month of his life."


As a result of some last-minute technical problems, Laika had to wait for the launch in the cabin for three days. The temperatures were low, and workers put a hose connected to a heater into the cockpit to keep her warm.


On Nov. 3, Laika blasted off into space in Sputnik 2, which weighed 1,118 pounds - a show of Soviet ability to take big payloads into space.


Sputnik 1 weighed just 184 pounds. The first U.S. satellite, Explorer 1, launched on Jan. 31, 1958, weighed about 31 pounds.


When Laika reached orbit, doctors found with relief that her pulse, which had risen on launch, and her blood pressure were normal. She ate specially prepared food from a container.


According to official Soviet reports, the dog was euthanized after a week. Laika's mission drew a wave of protests from animal protection activists in the West.


It wasn't until after the Soviet collapse, that some participants in the project told the true story: Laika indeed was to be euthanized with a programmed injection, but she apparently died of overheating after only a few hours in orbit. There was no information to indicate when exactly she died.


"It was impossible to build reliable life-support and thermal-control systems in such a short time," Chertok said in his memoirs.


Several other dogs died in failed launches before the successful space flight - and safe return to Earth - of Belka and Strelka in August 1960. After a few other flights with dogs, the Soviet Union put the world's first human - Yuri Gagarin - into space on April 12, 1961.


Gagarin is said to have joked: "I still don't understand who I am: the first human or the last dog in space."




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Sunday, November 4, 2007

Nanotechnology :MIT works toward 'smart' optical microchips


Light-powered micro-machines could advance telecommunications,


Rings, one millionth of a meter in size, are the moving parts of a 'smart' micromachine that could be powered and controlled by light on an optical chip. The rings move around and adapt to the color of light that is traveling through the bar, right.




A new theory developed at MIT could lead to "smart" optical microchips that adapt to different wavelengths of light, potentially advancing telecommunications, spectroscopy and remote sensing.

Postdocs Peter Rakich, left, and Milos Popovic of MIT's Research Laboratory of Electronics stand in front of a monitor that shows a demonstration of the way they propose to control microchips with light.




Drawn by the promise of superior system performance, researchers have been exploring the concept of microchips that manipulate light instead of electricity. In their new theory, the MIT team has shown how such chips could feature tiny machines with moving parts powered and controlled by the very light they manipulate, giving rise to fundamentally new functionality.

"There are thousands of complex functions we could make happen by tinkering with this idea," said Peter Rakich, an MIT postdoctoral associate who invented the theoretical concept along with postdoc Milos Popovic. The work was described in the cover story of the November issue of Nature Photonics.


For example, such chips could one day be used to remotely adjust the amount of bandwidth available in an optical network, or to automatically process signals flowing through fiber-optic networks, without using any electrical power, Rakich said.


Coauthors on the paper were Marin Soljacic, assistant professor of physics; and Erich Ippen, the Elihu Thomson Professor of Electrical Engineering and professor of physics.


"The idea that opto-nanomechanical devices can be designed to self-adapt to all-optical control--i.e., by self-aligning their resonances to optical control frequencies and by permitting all-optical tuning and dimension control--is new and exciting," said Ippen.


Earlier this year an MIT team composed of many of the same researchers showed that photonic circuitry could be integrated on a silicon chip by polarizing all of the light to the same orientation. The current work shows how tiny mobile machines can be built on such chips, taking advantage of the substantial pressures exerted by photons as they strike the walls of a cavity.


In the macroscopic world, light waves do not exert significant forces, but in the unique world of the microscopic, coupled with ultrapure laser light, photons bouncing off the walls of a cavity can build up a measurable force called radiation pressure. This is similar to the pressure exerted by gas molecules trapped in an aerosol can.


To take advantage of this radiation pressure, the researchers propose machines built from ring-shaped cavities only millionths of a meter in size located on the chip surface. When pressure on the cavity walls is high enough, the cavity is forced to move. This movement forms a critical part of an optical micromachine, which adjusts its configuration to respond to light in a predesigned way.


A unique application of this concept involves processing data that travels in fiber-optic networks. Today resonators employed in fiber-optic networks have to be synchronized with the incident light to ring at its frequency, in the same way an opera singer has to tune the pitch of her voice to make a wine glass ring.


Remarkably, a "smart" resonator based on the MIT concept could chase the frequency (color) of the laser light incident upon it. As the frequency of the laser beam changes, the frequency of the resonator will always follow it, no matter where it goes.


In other words, this new, unique resonator is like a wine glass that self-adjusts to the pitch of the singer's voice and follows it along throughout a song, Rakich said. He noted that physical systems that adapt to driving light and behave like these nanomachines do not exist elsewhere in nature.


By coupling the resonating cavities with nano-scale cantilevers, optical devices analogous to microelectromechanical systems (MEMS) devices can be created.


Although the researchers focused on ring-shaped cavities, their model could be applied to other structures as well.


"Our objective now is to develop a variety of light-powered micro- and nanomachines with unique capabilities enabled by this technology," explained Popovic. "But the first step will be to demonstrate the concept in practice."


The research was funded in part by the Army Research Office through MIT's Institute for Soldier Nanotechnologies.




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Friday, November 2, 2007

Nanotechnology, The new light to Revolutionize Natural Gas Industry


Nanotechnology ,The new light of the various solution has began to shows for future natural gas industry


Researchers from the University of Wyoming in the U.S. say that nanotechnology could present several opportunities for the natural gas industry, but that its use is hindered by lack of innovation in the industry, a perception of high cost, and a lack of awareness about nanotechnology. The researchers say that carbon nanotubes and porous engineered nanomaterials could be used to improve the efficiency of extraction in gas fields and other sources of natural gas. Additionally, they say that other nanomaterials could potentially be used to improve purification and storage of hydrocarbons, as well as for environmental remediation of pollutants.



Nanotechnology could revolutionize the natural gas industry across the whole lifecycle from extraction to pollution reduction or be an enormous missed opportunity, claim two industry experts writing in Inderscience's International Journal of Nanotechnology. They suggest that nanotechnology could help us extract more fuel and feedstock hydrocarbons from dwindling resources. However, industry inertia and a lack of awareness of the benefits could mean a missed opportunity.
According to Saeid Mokhatab and Brian Towler of the Chemical and Petroleum Engineering Department, at the University of Wyoming, in Laramie, there are many opportunities for the industry to exploit nanotechnology. However, there is a traditional lack of innovation in the exploration and production sector, a perception of high costs, new risks, and a general lack of awareness of the benefits of nanotechnology.


The researchers have now described the potential benefits of nanotechnology, which could change that perception. Mokhatab and Towler point out that nanomaterials, such as nanotubes or engineered porous minerals, might be used in the gas field or other source to improve the efficiency of extraction of a wide variety of hydrocarbon fuel compounds and chemical feedstocks.


Similarly, related nanomaterials might be used to improve purification and storage of hydrocarbons, while yet other nanomaterials might be used in environmental remediation, allowing contaminated sites to be cleaned up of harmful pollutants. Nanomaterials might even be developed as corrosion inhibitors for equipment and at the same time, more sophisticated nanotechnology could be developed as solid-state gas sensors for air pollution monitoring.


"The past decade has seen explosive growth worldwide in the synthesis and study of a wide range of nanostructured materials, the building blocks of nanotechnology," the researchers explain, "Investigations of mechanical, chemical, electrical, magnetic, and optical behaviour of nanostructured materials have demonstrated the possibilities to engineer the properties of these new materials for a wide range of applications."


The researchers add that as readily accessible hydrocarbon reserves become depleted, the oil and gas exploration and production industry faces increasing technical challenges. These challenges boil down to increased costs and limitations on drilling and production technologies.





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