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August 1, 2006, 11:09 PM CT

'vertically Oriented Nanoelectronics

'vertically Oriented Nanoelectronics
Engineers at Purdue University have developed a technique to grow individual carbon nanotubes vertically on top of a silicon wafer, a step toward making advanced electronics, wireless devices and sensors using nanotubes by stacking circuits and components in layers.

"Verticality gives you the ability to fit more things into the same area, so you can add more and more layers while keeping the footprint the same size or smaller," Fisher said. "But before we can even think about using nanotubes in electronics, we have to learn how to put them where we want them".

The engineers first created a "thin film" containing two layers of aluminum sandwiching one ultra-thin layer of iron using electron-beam evaporation, a standard process employed in the semiconductor industry. The engineers then used "anodization," a process that causes metals to oxidize - like rusting - to selectively create tiny cylindrical cavities and turn the film into a "porous anodic alumina template" less than 1/100th the width of a human hair in thickness. During the process, an electric field was used to form a precisely aligned array of nanoscopic holes, turning aluminum into porous alumina, the oxidized form of aluminum also known as aluminum oxide.

A mixture of hydrogen and methane gas was then flowed into the template's holes, and microwave energy was applied to break down the methane, which contains carbon. The iron layer acted as a catalyst that prompted the carbon nanotubes to assemble from carbon originating in the methane, and the tubes then grew vertically out of the cavities.........

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August 1, 2006, 9:42 PM CT

Grow Your-own Home

Grow Your-own Home This artist's rendering shows the Fab Tree Hab, a home made of living plants. Photo / Mitchell Joachim, courtesy Technology Review
In the future, homeowners may grow their houses instead of building them.

That's the vision of MIT architect Mitchell Joachim of the Media Lab's Smart Cities group. He and his colleagues -- environmental engineer Lara Greden (S.M. 2001, Ph.D. 2005) and architect Javier Arbona-Homar (S.M. 2004) -- have conceived a home that doesn't just use "green" design but is itself a living ecosystem. They call it the Fab Tree Hab.

The basic framework of the house would be created using a gardening method known as pleaching, in which young trees are woven together into a shape such as an archway, lattice, or screen and then encouraged to maintain that form over the years.

As the framework matured -- which might take a few years in tropical climates and several decades in more temperate locations -- the home grower would weave a dense layer of protective vines onto the exterior walls. Any gaps could be filled in with soil and growing plants to create miniature gardens. On the interior walls, a mixture of clay and straw beneath a final layer of smooth clay would provide insulation and block moisture. On south-facing walls, windows made of soy-based plastics would absorb warmth in the winter; ground-floor windows on the shady side could draw in cool breezes during hot months. Water collected on the roof would flow through the house for use by people and plants; wastewater would be purified in an outdoor pond with bacteria, fish and plants that consume organic waste.........

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August 1, 2006, 9:30 PM CT

A Splash With Robots

A Splash With Robots
A rousing game of underwater Quidditch brought this year's Minority Introduction to Engineering and Science program to a close on July 28.

High school students who had been working and living together at MIT for six weeks maneuvered their underwater robots through the Alumni Pool, picking up weighted markers and delivering them to a goal.

The event was just one in a daylong program that rounded out Minority Introduction to Engineering and Science (MITES).

The students, who will be seniors in the fall, also presented web site designs and a poster session on genomics to an appreciative audience in Room 34-101. The robot contest -- co-directed by Marc Graham (Ph.D. 2006), veteran competitor and teaching assistant in MIT's famed 2.007 robot contest, and Ed Moriarty, instructor in the Edgerton Center -- was broadcast to the room live on closed-circuit TV.

MITES was created in 1974 to increase the number of underrepresented minorities in the engineering professions by exposing students to engineering courses during their high school years.

The program is 100 percent scholarship-based. Funding from industry, foundations and individuals covers all expenses for each student.

This year's 62 high school juniors participated in a rigorous academic program at MIT, studying biology, calculus, chemistry, physics and engineering design among other science, engineering and computer science courses.........

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July 31, 2006, 10:28 PM CT

Summer Program For Young Researchers

Summer Program For Young Researchers
Celina Dozier, a chemical engineering major from Florida A&M University, has always known she wanted to come to MIT. This summer, thanks to the MIT Summer Research Program, she put her plan into action.

"There are so a number of resources here at MIT that we do not have at my university," said Dozier, who is spending her summer working on a research project in chemical engineering with Professor Paula Hammond and graduate student Marianne Terrot.

Dozier is at MIT along with 57 other university students from around the world as part of the annual MIT Summer Research Program (MSRP). The 2006 program started June 12 and runs through Aug. 13. MSRP interns work for two months with MIT faculty mentors on research projects in their respective fields.

Started in 1986, MSRP was part of an institutional effort to address the small numbers of African Americans, Mexican Americans, Native Americans and Puerto Ricans in engineering and science in the United States. In the past 20 years, 450 interns have gone through the program.

Over the years the program has grown and expanded. Now it is open to students with a broad array of backgrounds. In the past two years, MSRP has also doubled its enrollment with close to 60 interns participating in both 2005 and 2006.........

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July 29, 2006, 8:42 PM CT

More Efficient Production Of Electricity, Cold And Heat

More Efficient Production Of Electricity, Cold And Heat
IKERLAN-IK4 is taking part in a European project the aim of which is to design a single installation that will, at the same time, produce electricity, cold and heat for domestic use, while affording a notable reduction in environmental impact. In the PolySMART project, 32 organisations from eight European countries are participating, with a budget of 14.3 million euros and a projected period of four years.

Some large installations - sports centre, hotels and large industry - already use systems capable of generating both electricity and refrigeration for air conditioning and heat for heating and hot sanitary. This integrated, trigeneration system provides significant energy and environmental advantages. However, for domestic use, its installation meets many problems.

With its participation in PolySMART, the IKERLAN-IK4 Centre for Technological Research aims to overcome these difficulties and barriers to the home installation of the energy-saving technology and demonstrate that is economically, technically and environmentally viable to adapt these installations to individual household consumption. Its main objective is to achieve a single installation that supplies all the energy demands in our homes. To this end, other centres of reference in the field of energy in buildings are collaborating, such as the German Fraunhofer-ISF or the Dutch ECN. Another two companies from the Spanish State are working together with IKERLAN-IK4 - Rotartica and Besel.........

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July 29, 2006, 8:36 PM CT

Insights Into Granicus And Tinjar Valles

Insights Into Granicus And Tinjar Valles
Granicus Valles and Tinjar Valles

For high resolution images See this page

These images, taken by the High Resolution Stereo Camera (HRSC) on board ESA's Mars Express spacecraft, show the regions of Granicus Valles and Tinjar Valles, which may have been formed partly through the action of subsurface water, due to a process known as sapping.

The HRSC obtained these images during orbit 1383 at a ground resolution of approximately 23.7 metres per pixel. The images have been rotated 90 degrees counter-clockwise, so that North is to the left.

They show the regions of Granicus Valles and Tinjar Valles, lying at approximately 26.8 degree North and 135.7 degree East. The northwest-aligned Granicus Valles and Tinjar Valles are part of the Utopia-Planitia region, an area thought to be covered by a layer of lava that flowed from the northwest flanks of Elysium Mons into the Utopia-Planitia Basin.

Today, this once-smooth volcanic plain is incised by channels of variable size and appearance, including Granicus Valles (towards the West) and Tinjar Valles (towards the North).

Both channel systems evolve from a single main channel entering the image scene from southeast (upper right), exhibiting an approximate width of 3 km and extending 300 m below the surrounding terrain at maximum. The impressive sinuous lava channel emanates from the mouth of a radial, a circular drainage area, and runs to the Elysium rise trending into a graben, which is terrain dissected by tectonic deformation.........

Posted by: Edwin      Permalink         Source


July 29, 2006, 8:25 PM CT

Insights Into Scientific Revolution

Insights Into Scientific Revolution
With the "Genesis of General Relativity", the Max Planck Institute for the History of Science (MPIWG) has just published the most comprehensive study to date of the structures of a scientific revolution. As per the study, a scientific revolution is not a simple radical new beginning, but the result of a new organisation of transmitted knowledge. The result of 10 years of research, this four-volume, 2000-page work on the origins of Einstein's General Relativity Theory - one of the most important physical theories of the 20th century - will appear in the Springer Press. Jürgen Renn, Director at the Max Planck Institute, will present the work, of which he is also the editor, to the scientific public at the 11th Marcel Grossmann Meetings, which will take place in Berlin on 24 - 29 July, 2006. The work, which is the result of an international team of authors, contains new insights into the premises, assumptions, and preconditions that underlie Einstein's scientific revolution, as, for instance, insights into the role of Einstein's previously largely unknown precursors and competitors for a theory which today represents the basis of modern cosmology.

"Einstein did not achieve this revolution by means of a single stroke of genius-rather, he stood on the shoulders of dwarves and giants", says Jürgen Renn. Volumes 1 and 2 contain the facsimile and transcription of, as well as a scholarly commentary on, Einstein's famous Zurich Notebook from 1912-1913. The research by Einstein recorded in this notebook forms a pivotal part of his creation of the theory of general relativity. Complementing this core material are essays re-evaluating the genesis of Einstein's theory in light of the analysis of this notebook. Volumes 3 and 4 contain additional sources by Einstein and his contemporaries, who from the late nineteenth to the early twentieth century contributed to this groundbreaking development. These sources, most of which are presented here in translation for the first time, are accompanied by essays by leading historians of relativity offering new insights into the broader scientific context from which Einstein's theory emerged. The result of more than a decade of research, these four volumes provide a study of unprecedented depth of one of the most important revolutions in the history of science.........

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July 28, 2006, 10:09 PM CT

From Farm Waste To Bio-oil

From Farm Waste To Bio-oil
Samy Sadaka reached into a garbage bag, picked up a mixture of cow manure and corn stalks, let it run through his fingers and invited a visitor to do the same.

It wasn't that bad.

That mix of manure and corn stalks had spent 27 days breaking down in a special drying process. The end result looked like brown yard mulch with lots of thin fibers. There wasn't much smell. And it was dry to the touch.

"That's about 20 percent moisture," said Drew Simonsen, an Iowa State University sophomore from Quimby who's working on the research project led by Sadaka, an associate scientist for Iowa State's Center for Sustainable Environmental Technologies.

Other Iowa State scientists working on the project are Robert Burns, an associate professor of agricultural and biosystems engineering; Mark Hanna, an Extension agricultural engineer; Robert C. Brown, director of the Center for Sustainable Environmental Technologies and Bergles Professor in Thermal Science; and Hee-Kwon Ahn, a postdoctoral researcher for the department of agricultural and biosystems engineering.

The project is being supported by $190,000 in grants from the Iowa Biotechnology Byproducts Consortium.

The scientists are working to take wastes from Iowa farms -- manure and corn stalks -- and turn them into a bio-oil that could be used for boiler fuel and perhaps transportation fuel.........

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July 28, 2006, 9:47 PM CT

Making Clearer Pictures

Making Clearer Pictures
Software makes pictures clearer.

Software helps astronomers see what's hidden in noisy and blurred images of stars and galaxies. Metropolis Data Consultants uses the same techniques to give doctors and the police clearer pictures to work on.

Astronomers use all sorts of telescopes to explore outer space. Some are optical telescopes - bigger and better versions of those you might have at home. Using lenses and mirrors, they make distant objects seem much nearer than they are.

Other telescopes look for radio waves, x-rays and other types of radiation. They give astronomers a different view of the universe - one that deepens their understanding.

But whichever they use, the problem for astronomers is the same. When they're looking at faint objects far out into space, they don't get perfect pictures.

Blur and noise.

To start with, things move. The Earth is rotating, for example, and the satellites that carry telescopes aren't absolutely stationary. Blurring is inevitable.

To make things even worse, some kinds of telescope add noise to the picture. When the image itself is faint, the result is the sort of picture you get when your TV isn't tuned in properly. You can see that something is there but you can't see it clearly.........

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July 26, 2006, 10:20 PM CT

Recording License Plates A Snap

Recording License Plates A Snap Supervisory Customs Inspector Joseph Misenhelter and Under Secretary for Enforcement Jimmy Gurule observe traffic passing through the LPRs.
Keeping an eye on travelers in approaching vehicles while locating and manually entering license plate numbers is a especially challenging task for Customs inspectors. Correct entry of these plates is critical in ensuring they are crosschecked in the Treasury Enforcement Communications System (TECS) and the National Crime Information Center (NCIC) databases for possible matches with potential criminal suspects. While inspectors have an excellent record of meeting this challenge, Customs continues to search for ways to make our data more accurate and the inspector's job safer - the latest development toward that goal is the Customs License Plate Readers (LPR) System.

Manual entry of plates compromises eye contact with approaching traffic. With the LPR reading and recording vehicle plates, the Customs inspector can give more attention to other vital border inspection duties like maintaining eye contact with the vehicle, and its occupants. Years in development, the LPR has demonstrated reading accuracy of over 90 percent of vehicle license plates, whether traffic is incoming or outgoing.

The LPR includes five different components that help capture license plate data and convert it to an electronic format to cross check the TECS and NCIC databases for possible record matches. On average, the complete process takes less than a second.........

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