Scientists have discovered the most effective method yet to convert glucose, found in plants worldwide and nature’s most abundant sugar, to HFM, a chemical that can be broken into components for products now made from petroleum. Image Credit: Pacific Northwest National Laboratory
Hydroxymethylfurfural - A Substance For The Ages
Oil has become the root substance of our modern society. The compounds not only fuel our automobiles, they are the building blocks that form plastics and chemical compounds that make modern life easier.
Corn and other plant material, when distilled to make Ethanol, have been heralded as the replacement for gasoline for our cars but what if we were able to use plant material for more … much more.
Well, scientists at the The Pacific Northwest National Laboratory in Richland Washington is a US Department of Energy (DOE) government research laboratory, have released an article to the journal, Science, that describes just this breakthrough.
Scientists have discovered the most effective method yet to convert glucose, found in plants worldwide and nature's most abundant sugar, to Hydroxymethylfurfural - HMF, a chemical that can be broken into components for products now made from petroleum.
Excerpts from press release issued from The Pacific Northwest National Laboratory (PNNL) -
Scientists get plastic from trees
Submitted by Vidura Panditaratne - PNNL - Fri, 2007-06-15
The researchers at PNNL-based Institute for Interfacial Catalysis, or IIC, took a giant step closer to the biorefinery when they directly converted sugars ubiquitous in nature to an alternative source for those products that make oil so valuable, with very little of the residual impurities that have made the quest so daunting.
“What we have done that no one else has been able to do is convert glucose directly in high yields to a primary building block for fuel and polyesters,” said Z. Conrad Zhang [Chief Scientist - Institute for Interfacial Catalysis, Pacific Northwest National Lab], senior author who led the research.
That building block is called HMF, which stands for hydroxymethylfurfural. It is a chemical derived from carbohydrates such as glucose and fructose and is viewed as a promising surrogate for petroleum-based chemicals.
Glucose, in plant starch and cellulose, is nature’s most abundant sugar. “But getting a commercially viable yield of HMF from glucose has been very challenging,” Zhang said. “In addition to low yield until now, we always generate many different byproducts,” including levulinic acid, making product purification expensive and uncompetitive with petroleum-based chemicals.
Zhang, lead author and former post doc Haibo Zhao, and colleagues John Holladay and Heather Brown, all from PNNL, were able to coax HMF yields upward of 70 percent from glucose and nearly 90 percent from fructose while leaving only traces of acid impurities. To achieve this, they experimented with a novel non-acidic catalytic system containing metal chloride catalysts in a solvent capable of dissolving cellulose.
The solvent, called an ionic liquid, enabled the metal chlorides to convert the sugars to HMF. Ionic liquids provide an additional benefit: It is reusable, thus produces none of the wastewater in other methods that convert fructose to HMF.
----
“This, in my view, is breakthrough science in the renewable energy arena,” said J.M. White, IIC director and Robert A. Welch chair in materials chemistry at the University of Texas. “This work opens the way for fundamental catalysis science in a novel solvent.”
The chemistry at work remains largely a mystery, Zhang said, but he suspects that metal chloride catalysts work during an atom-swapping phase that sugar molecules go through called mutarotation, in which an H (hydrogen) and OH (hydroxyl group) trade places.
----
“The key is to take advantage of the open form to perform a hydride transfer through which glucose is converted to fructose.”
Zhang’s next step is to tinker with ionic solvents and metal halides combinations to see if he can increase HMF yield from glucose while reducing separation and purification cost.
“The opportunities are endless,” Zhang said, “and the chemistry is starting to get interesting.”
Read All>>
Sunday, June 17, 2007
Tuesday, June 12, 2007
Stick-Pin Tour & Travel Planning Made Easy
The Brooklyn Museum exhibition Graffiti looked at graffiti as a phenomenon of modern urban life. During the exhibition, June 30 - September 3, 2006, we invited the Brooklyn and Flickr communities to share their photographs of existing graffiti and/or murals around the borough of Brooklyn. This photograph of Brooklyn-area graffiti was submitted by a community member. Image Credit: Flickr
Stick-Pin Tour & Travel Planning Made Easy
People love to photograph their travels, especially in this digital age. Increasingly, people are posting their travel photos on photo posting portals like Flickr, SmugMug, & Everytrail … and, what is really cool, adding locater tags along with GPS data to the photos they upload.
What makes this really cool is that it is much easier to plan a tour in a particular travel destination tailored to ones specific interests. It’s easy - just type in a few tags into the Google, Flickr, SmugMug, and etc. search window and behold locations one can plot to create a tour of ones interest.
The planning and search process is pretty simple because the work is done through the meta-data travelers are eager to provide for being able to find and identify the photo they took to share with others they know … the extended benefit is everyone else’s gain.
Excerpts from The New York Times via CNET News.com -
Snapshots that do more than bore friends
How sharing your family vacation photos online can help others discover a place through your travels.
The New York Times - By Michelle Higgins - Published: June 9, 2007, 11:42 AM PDT
Few sentences in the English language are more dreaded than this seemingly innocent offer: "Oh, I must show you the pictures from my vacation." Who wants to see endless shots of a friend lounging by a pool or in front of a monument, or -- worse yet -- their kids doing the very same things?
But, of course, those very same shots can be extremely useful when researching your own trip. How big is that pool? What, exactly, does the room at that five-star hotel you're thinking of booking look like? What's the crowd like at the so-called hot restaurant? It's good to have documented evidence from someone who has been there.
----
Through a technology called geotagging, users can add GPS data to their pictures, which can then be plotted on a digital map. This not only allows users to see exactly where a photo was taken, but, when uploaded to an Internet map, users can also quickly browse a trove of photos that were taken nearby, providing a kind of scattershot collage of a place.
For example, people planning a trip to Cancun can use Google Earth, a free mapping software, to zoom in on Cancun's crowded hotel zone and click on dozens of candid photographs, from the lounge chairs at the Fiesta Americana Grand Coral Beach hotel and the pool at the Omni Hotel & Villas, to snapshots of less crowded beaches and the nearest mall.
Plotting photos on maps also allows trip planners to "see" the terrain before booking a trip. On Everytrail.com -- which lets users upload geocoded photos from their favorite hiking trails, biking routes and sailing trips -- visitors can check out sights along a specific driving route in Namibia, or examine trail conditions on a hilly bike route near Palo Alto, Calif.
----
“Gowanus” - This photograph of Brooklyn-area graffiti was submitted by a community member. The Brooklyn Museum exhibition - Graffiti. Image Credit: Flickr
For example, fans of graffiti can search the word, "graffiti," and "New York City" at Flickr.com/map, and pull up photos of freshly painted tags, all plotted with pushpins on a clickable Yahoo map. A search for "Dumbo Brooklyn graffiti," for example, finds some 99 photos, including the infamous "Neck Face" tag, spray-painted on a brick warehouse at Jay and Front Streets in Brooklyn. Try finding that in a guidebook.
"Dumbo Brooklyn graffiti" – Photo of screenshot search for tourpoint locations. Image Credit: Edmund Jenks (MAXINE)
Geotagging photos brings a whole new level of context to the image, said Andy Williams, general manager of SmugMug.com, a photo-sharing site. "After all," he said, "pictures are flat." But the real reason geotagging is getting so popular, he added, are the bragging rights involved. "We want people to know the cool places we've been," he said. "And this is a cool way to show off."
----
The steps needed to geotag photos are admittedly somewhat geeky.
----
To streamline the process, several camera makers have released models that are GPS-ready, with either a built-in device or a special accessory. But they tend to be geared toward professionals and are expensive.
----
Once your photos are plotted geographically, others can discover a place through your travels.
----
Web sites are increasingly embracing geotagging as a way to draw users. Last month, Google announced plans to acquire Panoramio.com, a photo-sharing site with more than two million images that allows users to integrate photos into Google Earth. And as photo-sharing continues to evolve, travel Web sites are recognizing how valuable images can be when users essentially act as free contributors and submit their own pictures.
Zoomandgo.com, a travel review site, recently redesigned its site around photos and videos submitted by travelers. A team of four people spent months "geocoding" thousands of hotels and attractions so that user photos can be displayed on digital maps. A new social-networking feature also allows users to create their own travel profiles, connect with like-minded travelers, and swap tips through photos.
"Facebook meets Frommers" is how Jonathan Haldane, the founder of Zoomandgo.com, described it. Before the social-networking feature went up, he said, users spent about eight minutes on the site, mostly reading or posting hotel reviews. Now, he said, users spend an average of 18 to 19 minutes, sending messages to each other and browsing through photos and videos.
But though travel sites are embracing the flood of user-generated photos, the quality can vary. A Flickr search for the W hotel in New York City, for example, turns up a mix of candid room photos and pictures of friends eating pizza
----
Zoomandgo.com, which pays users a nominal fee for relevant photos, says it vets every submission.
----
Panoramio, on the other hand, has a devoted online community that tends to self-edit, and post photos only of places rather than people.
Reference Here>>
Stick-Pin Tour & Travel Planning Made Easy
People love to photograph their travels, especially in this digital age. Increasingly, people are posting their travel photos on photo posting portals like Flickr, SmugMug, & Everytrail … and, what is really cool, adding locater tags along with GPS data to the photos they upload.
What makes this really cool is that it is much easier to plan a tour in a particular travel destination tailored to ones specific interests. It’s easy - just type in a few tags into the Google, Flickr, SmugMug, and etc. search window and behold locations one can plot to create a tour of ones interest.
The planning and search process is pretty simple because the work is done through the meta-data travelers are eager to provide for being able to find and identify the photo they took to share with others they know … the extended benefit is everyone else’s gain.
Excerpts from The New York Times via CNET News.com -
Snapshots that do more than bore friends
How sharing your family vacation photos online can help others discover a place through your travels.
The New York Times - By Michelle Higgins - Published: June 9, 2007, 11:42 AM PDT
Few sentences in the English language are more dreaded than this seemingly innocent offer: "Oh, I must show you the pictures from my vacation." Who wants to see endless shots of a friend lounging by a pool or in front of a monument, or -- worse yet -- their kids doing the very same things?
But, of course, those very same shots can be extremely useful when researching your own trip. How big is that pool? What, exactly, does the room at that five-star hotel you're thinking of booking look like? What's the crowd like at the so-called hot restaurant? It's good to have documented evidence from someone who has been there.
----
Through a technology called geotagging, users can add GPS data to their pictures, which can then be plotted on a digital map. This not only allows users to see exactly where a photo was taken, but, when uploaded to an Internet map, users can also quickly browse a trove of photos that were taken nearby, providing a kind of scattershot collage of a place.
For example, people planning a trip to Cancun can use Google Earth, a free mapping software, to zoom in on Cancun's crowded hotel zone and click on dozens of candid photographs, from the lounge chairs at the Fiesta Americana Grand Coral Beach hotel and the pool at the Omni Hotel & Villas, to snapshots of less crowded beaches and the nearest mall.
Plotting photos on maps also allows trip planners to "see" the terrain before booking a trip. On Everytrail.com -- which lets users upload geocoded photos from their favorite hiking trails, biking routes and sailing trips -- visitors can check out sights along a specific driving route in Namibia, or examine trail conditions on a hilly bike route near Palo Alto, Calif.
----
“Gowanus” - This photograph of Brooklyn-area graffiti was submitted by a community member. The Brooklyn Museum exhibition - Graffiti. Image Credit: Flickr
For example, fans of graffiti can search the word, "graffiti," and "New York City" at Flickr.com/map, and pull up photos of freshly painted tags, all plotted with pushpins on a clickable Yahoo map. A search for "Dumbo Brooklyn graffiti," for example, finds some 99 photos, including the infamous "Neck Face" tag, spray-painted on a brick warehouse at Jay and Front Streets in Brooklyn. Try finding that in a guidebook.
"Dumbo Brooklyn graffiti" – Photo of screenshot search for tourpoint locations. Image Credit: Edmund Jenks (MAXINE)
Geotagging photos brings a whole new level of context to the image, said Andy Williams, general manager of SmugMug.com, a photo-sharing site. "After all," he said, "pictures are flat." But the real reason geotagging is getting so popular, he added, are the bragging rights involved. "We want people to know the cool places we've been," he said. "And this is a cool way to show off."
----
The steps needed to geotag photos are admittedly somewhat geeky.
----
To streamline the process, several camera makers have released models that are GPS-ready, with either a built-in device or a special accessory. But they tend to be geared toward professionals and are expensive.
----
Once your photos are plotted geographically, others can discover a place through your travels.
----
Web sites are increasingly embracing geotagging as a way to draw users. Last month, Google announced plans to acquire Panoramio.com, a photo-sharing site with more than two million images that allows users to integrate photos into Google Earth. And as photo-sharing continues to evolve, travel Web sites are recognizing how valuable images can be when users essentially act as free contributors and submit their own pictures.
Zoomandgo.com, a travel review site, recently redesigned its site around photos and videos submitted by travelers. A team of four people spent months "geocoding" thousands of hotels and attractions so that user photos can be displayed on digital maps. A new social-networking feature also allows users to create their own travel profiles, connect with like-minded travelers, and swap tips through photos.
"Facebook meets Frommers" is how Jonathan Haldane, the founder of Zoomandgo.com, described it. Before the social-networking feature went up, he said, users spent about eight minutes on the site, mostly reading or posting hotel reviews. Now, he said, users spend an average of 18 to 19 minutes, sending messages to each other and browsing through photos and videos.
But though travel sites are embracing the flood of user-generated photos, the quality can vary. A Flickr search for the W hotel in New York City, for example, turns up a mix of candid room photos and pictures of friends eating pizza
----
Zoomandgo.com, which pays users a nominal fee for relevant photos, says it vets every submission.
----
Panoramio, on the other hand, has a devoted online community that tends to self-edit, and post photos only of places rather than people.
Reference Here>>
Sunday, June 10, 2007
Blue Areas On The Red Orb
Smooth bluish areas on a Martian crater floor could be ponds, according to two scientists. The area is approximately 1 square metre – Image Credit: Ron Levin (as appeared in article, New Scientist)
Blue Areas On The Red Orb
A deeper analysis of the images taken on Mars surface (JPL website) stir the debate on whether there is standing water … puddles of water on Mars.
In a report to be published in the journal IEEE Xplore, R. L. Levin and Daniel Lyddy detail their investigation of possible liquid water ponds on the Martian surface (2007 IEEE Aerospace Applications Conference Proceedings, paper #1376).
Through stereoscopic reconstruction of the images captured by the Mars Rover, Opportunity, Lockheed engineers were able to highlight surface details that just might prove the existence of water on Mars.
Excerpts from the New Scientist –
Mars rover finds "puddles" on the planet's surface
By David Chandler - NewScientist.com news service - 15:33 08 June 2007
The report identifies specific spots that appear to have contained liquid water two years ago, when Opportunity was exploring a crater called Endurance. It is a highly controversial claim, as many scientists believe that liquid water cannot exist on the surface of Mars today because of the planet’s thin atmosphere.
If confirmed, the existence of such ponds would significantly boost the odds that living organisms could survive on or near the surface of Mars, says physicist Ron Levin, the report's lead author, who works in advanced image processing at the aerospace company Lockheed Martin in Arizona.
Along with fellow Lockheed engineer Daniel Lyddy, Levin used images from the Jet Propulsion Laboratory's website. The resulting stereoscopic reconstructions, made from paired images from the Opportunity rover's twin cameras, show bluish features that look perfectly flat. The surfaces are so smooth that the computer could not find any surface details within those areas to match up between the two images.
The imaging shows that the areas occupy the lowest parts of the terrain. They also appear transparent: some features, which Levin says may be submerged rocks or pebbles, can be seen below the plane of the smooth surface.
Smooth surface - The smoothness and transparency of the features could suggest either water or very clear ice, Levin says.
"The surface is incredibly smooth, and the edges are in a plane and all at the same altitude," he says. "If they were ice or some other material, they'd show wear and tear over the surface, there would be rubble or sand or something."
His report was presented at a conference of the Institute of Electrical and Electronics Engineers, and will be published later this year in the institute's proceedings.
----
Speedy evaporation? - Levin and other reasearchers, including JPL's Michael Hecht, have published calculations showing the possibility of "micro-environments" where water could linger, but the idea remains controversial.
“The temperatures get plenty warm enough, but the Mars atmosphere is essentially a vacuum," says Phil Christensen of Arizona State University, developer of the Mars rovers' mini-Thermal Emission Spectrometers. That means any water or ice exposed on the surface evaporates or sublimes away almost instantly, he says.
----
If there were absolutely no wind, says Christensen, you might build up a stagnant layer of vapour above a liquid surface, preventing it from evaporating too fast. “The problem is, there are winds on Mars… In the real world, I think it's virtually impossible," he told New Scientist.
Simple test - Levin disagrees. He says his analysis shows that there can be wind-free environments at certain times of day in certain protected locations. He thinks that could apply to these small depressions inside the sheltered bowl of Endurance crater, at midday in the Martian summer.
He adds that highly briny water, as is probably found on Mars, could be stable even at much lower temperatures.
Although the rover is now miles away from this site, Levin proposes a simple test that would prove the presence of liquid if similar features are found: use the rover's drill on the surface of the flat area. If it is ice, or any solid material, the drill will leave unmistakable markings, but if it is liquid there should be no trace of the drill's activity.
Reference Here>>
Blue Areas On The Red Orb
A deeper analysis of the images taken on Mars surface (JPL website) stir the debate on whether there is standing water … puddles of water on Mars.
In a report to be published in the journal IEEE Xplore, R. L. Levin and Daniel Lyddy detail their investigation of possible liquid water ponds on the Martian surface (2007 IEEE Aerospace Applications Conference Proceedings, paper #1376).
Through stereoscopic reconstruction of the images captured by the Mars Rover, Opportunity, Lockheed engineers were able to highlight surface details that just might prove the existence of water on Mars.
Excerpts from the New Scientist –
Mars rover finds "puddles" on the planet's surface
By David Chandler - NewScientist.com news service - 15:33 08 June 2007
The report identifies specific spots that appear to have contained liquid water two years ago, when Opportunity was exploring a crater called Endurance. It is a highly controversial claim, as many scientists believe that liquid water cannot exist on the surface of Mars today because of the planet’s thin atmosphere.
If confirmed, the existence of such ponds would significantly boost the odds that living organisms could survive on or near the surface of Mars, says physicist Ron Levin, the report's lead author, who works in advanced image processing at the aerospace company Lockheed Martin in Arizona.
Along with fellow Lockheed engineer Daniel Lyddy, Levin used images from the Jet Propulsion Laboratory's website. The resulting stereoscopic reconstructions, made from paired images from the Opportunity rover's twin cameras, show bluish features that look perfectly flat. The surfaces are so smooth that the computer could not find any surface details within those areas to match up between the two images.
The imaging shows that the areas occupy the lowest parts of the terrain. They also appear transparent: some features, which Levin says may be submerged rocks or pebbles, can be seen below the plane of the smooth surface.
Smooth surface - The smoothness and transparency of the features could suggest either water or very clear ice, Levin says.
"The surface is incredibly smooth, and the edges are in a plane and all at the same altitude," he says. "If they were ice or some other material, they'd show wear and tear over the surface, there would be rubble or sand or something."
His report was presented at a conference of the Institute of Electrical and Electronics Engineers, and will be published later this year in the institute's proceedings.
----
Speedy evaporation? - Levin and other reasearchers, including JPL's Michael Hecht, have published calculations showing the possibility of "micro-environments" where water could linger, but the idea remains controversial.
“The temperatures get plenty warm enough, but the Mars atmosphere is essentially a vacuum," says Phil Christensen of Arizona State University, developer of the Mars rovers' mini-Thermal Emission Spectrometers. That means any water or ice exposed on the surface evaporates or sublimes away almost instantly, he says.
----
If there were absolutely no wind, says Christensen, you might build up a stagnant layer of vapour above a liquid surface, preventing it from evaporating too fast. “The problem is, there are winds on Mars… In the real world, I think it's virtually impossible," he told New Scientist.
Simple test - Levin disagrees. He says his analysis shows that there can be wind-free environments at certain times of day in certain protected locations. He thinks that could apply to these small depressions inside the sheltered bowl of Endurance crater, at midday in the Martian summer.
He adds that highly briny water, as is probably found on Mars, could be stable even at much lower temperatures.
Although the rover is now miles away from this site, Levin proposes a simple test that would prove the presence of liquid if similar features are found: use the rover's drill on the surface of the flat area. If it is ice, or any solid material, the drill will leave unmistakable markings, but if it is liquid there should be no trace of the drill's activity.
Reference Here>>
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Tuesday, June 5, 2007
Hear This! Converting Waste Heat Into Electric Power
University of Utah physicist Orest Symko demonstrates how heat can be converted into sound by using a blowtorch to heat a metallic screen inside a plastic tube, which then produces a loud tone, similar to when air is blown into a flute. Symko and his students are developing much smaller devices that not only convert heat to sound, but then use the sound to generate electricity. The devices may be used to cool electronics, harness solar energy in a new way, and conserve energy by changing waste heat into electric power. Image Credit: University of Utah
Hear This! Converting Waste Heat Into Electric Power
It sounds like magic but it is really science.
The University of Utah Physics Department has developed a way for devices to take wasted heat derived from everyday processes and through converting the heat to sound … one can then convert the sound to usable electricity.
The US Army is interested in funding this research activity because it is interested in taking care of the wasted heat from radar operations in the field, and also producing a portable source of electrical energy which one can use in the battlefield to run electronics.
The process utilizes two steps with processes called "thermoacoustic prime movers" and "piezoelectric" devices.
Excerpts from Science Daily (the story has been adapted from a news release issued by University of Utah) -
A Sound Way To Turn Heat Into Electricity
Science Daily, June 4, 2007
University of Utah physicists developed small devices that turn heat into sound and then into electricity. The technology holds promise for changing waste heat into electricity, harnessing solar energy and cooling computers and radars.
"We are converting waste heat to electricity in an efficient, simple way by using sound," says Orest Symko, a University of Utah physics professor who leads the effort. "It is a new source of renewable energy from waste heat."
Five of Symko's doctoral students recently devised methods to improve the efficiency of acoustic heat-engine devices to turn heat into electricity. They will present their findings on Friday, June 8 during the annual meeting of the Acoustical Society of America at the Hilton Salt Lake City Center hotel.
Symko plans to test the devices within a year to produce electricity from waste heat at a military radar facility and at the university's hot-water-generating plant.
----
Symko expects the devices could be used within two years as an alternative to photovoltaic cells for converting sunlight into electricity. The heat engines also could be used to cool laptop and other computers that generate more heat as their electronics grow more complex. And Symko foresees using the devices to generate electricity from heat that now is released from nuclear power plant cooling towers.
How to Get Power from Heat and Sound
Symko's work on converting heat into electricity via sound stems from his ongoing research to develop tiny thermoacoustic refrigerators for cooling electronics.
----
In 2005, he began a five-year heat-sound-electricity conversion research project named Thermal Acoustic Piezo Energy Conversion (TAPEC). Symko works with collaborators at Washington State University and the University of Mississippi.
The project has received $2 million in funding during the past two years, and Symko hopes it will grow as small heat-sound-electricity devices shrink further so they can be incorporated in micromachines (known as microelectromechanical systems, or MEMS) for use in cooling computers and other electronic devices such as amplifiers.
Using sound to convert heat into electricity has two key steps. Symko and colleagues developed various new heat engines (technically called "thermoacoustic prime movers") to accomplish the first step: convert heat into sound.
Then they convert the sound into electricity using existing technology: "piezoelectric" devices that are squeezed in response to pressure, including sound waves, and change that pressure into electrical current. "Piezo" means pressure or squeezing.
Most of the heat-to-electricity acoustic devices built in Symko's laboratory are housed in cylinder-shaped "resonators" that fit in the palm of your hand. Each cylinder, or resonator, contains a "stack" of material with a large surface area -- such as metal or plastic plates, or fibers made of glass, cotton or steel wool -- placed between a cold heat exchanger and a hot heat exchanger.
When heat is applied -- with matches, a blowtorch or a heating element -- the heat builds to a threshold. Then the hot, moving air produces sound at a single frequency, similar to air blown into a flute.
"You have heat, which is so disorderly and chaotic, and all of a sudden you have sound coming out at one frequency," Symko says.
Then the sound waves squeeze the piezoelectric device, producing an electrical voltage. Symko says it's similar to what happens if you hit a nerve in your elbow, producing a painful electrical nerve impulse.
----
Devices that convert heat to sound and then to electricity lack moving parts, so such devices will require little maintenance and last a long time.
----
Symko says the devices won't create noise pollution. First, as smaller devices are developed, they will convert heat to ultrasonic frequencies people cannot hear. Second, sound volume goes down as it is converted to electricity. Finally, "it's easy to contain the noise by putting a sound absorber around the device," he says.
Read All>>
Hear This! Converting Waste Heat Into Electric Power
It sounds like magic but it is really science.
The University of Utah Physics Department has developed a way for devices to take wasted heat derived from everyday processes and through converting the heat to sound … one can then convert the sound to usable electricity.
The US Army is interested in funding this research activity because it is interested in taking care of the wasted heat from radar operations in the field, and also producing a portable source of electrical energy which one can use in the battlefield to run electronics.
The process utilizes two steps with processes called "thermoacoustic prime movers" and "piezoelectric" devices.
Excerpts from Science Daily (the story has been adapted from a news release issued by University of Utah) -
A Sound Way To Turn Heat Into Electricity
Science Daily, June 4, 2007
University of Utah physicists developed small devices that turn heat into sound and then into electricity. The technology holds promise for changing waste heat into electricity, harnessing solar energy and cooling computers and radars.
"We are converting waste heat to electricity in an efficient, simple way by using sound," says Orest Symko, a University of Utah physics professor who leads the effort. "It is a new source of renewable energy from waste heat."
Five of Symko's doctoral students recently devised methods to improve the efficiency of acoustic heat-engine devices to turn heat into electricity. They will present their findings on Friday, June 8 during the annual meeting of the Acoustical Society of America at the Hilton Salt Lake City Center hotel.
Symko plans to test the devices within a year to produce electricity from waste heat at a military radar facility and at the university's hot-water-generating plant.
----
Symko expects the devices could be used within two years as an alternative to photovoltaic cells for converting sunlight into electricity. The heat engines also could be used to cool laptop and other computers that generate more heat as their electronics grow more complex. And Symko foresees using the devices to generate electricity from heat that now is released from nuclear power plant cooling towers.
How to Get Power from Heat and Sound
Symko's work on converting heat into electricity via sound stems from his ongoing research to develop tiny thermoacoustic refrigerators for cooling electronics.
----
In 2005, he began a five-year heat-sound-electricity conversion research project named Thermal Acoustic Piezo Energy Conversion (TAPEC). Symko works with collaborators at Washington State University and the University of Mississippi.
The project has received $2 million in funding during the past two years, and Symko hopes it will grow as small heat-sound-electricity devices shrink further so they can be incorporated in micromachines (known as microelectromechanical systems, or MEMS) for use in cooling computers and other electronic devices such as amplifiers.
Using sound to convert heat into electricity has two key steps. Symko and colleagues developed various new heat engines (technically called "thermoacoustic prime movers") to accomplish the first step: convert heat into sound.
Then they convert the sound into electricity using existing technology: "piezoelectric" devices that are squeezed in response to pressure, including sound waves, and change that pressure into electrical current. "Piezo" means pressure or squeezing.
Most of the heat-to-electricity acoustic devices built in Symko's laboratory are housed in cylinder-shaped "resonators" that fit in the palm of your hand. Each cylinder, or resonator, contains a "stack" of material with a large surface area -- such as metal or plastic plates, or fibers made of glass, cotton or steel wool -- placed between a cold heat exchanger and a hot heat exchanger.
When heat is applied -- with matches, a blowtorch or a heating element -- the heat builds to a threshold. Then the hot, moving air produces sound at a single frequency, similar to air blown into a flute.
"You have heat, which is so disorderly and chaotic, and all of a sudden you have sound coming out at one frequency," Symko says.
Then the sound waves squeeze the piezoelectric device, producing an electrical voltage. Symko says it's similar to what happens if you hit a nerve in your elbow, producing a painful electrical nerve impulse.
----
Devices that convert heat to sound and then to electricity lack moving parts, so such devices will require little maintenance and last a long time.
----
Symko says the devices won't create noise pollution. First, as smaller devices are developed, they will convert heat to ultrasonic frequencies people cannot hear. Second, sound volume goes down as it is converted to electricity. Finally, "it's easy to contain the noise by putting a sound absorber around the device," he says.
Read All>>
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